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Virological point-of-care testing for the
developing world
Marycelin M Baba1, Nina Vidergar2 & Alessandro Marcello*,2
ABSTRACT: The goal of point-of-care testing is to provide fast, convenient, and easy-touse diagnostic assays that shorten the turnaround time of intervention. Several diagnostic
tests have already migrated from the centralized laboratory to patients’ bedside, physician
oices and domestic environments in more developed countries. However, the situation
is dramatically diferent in countries of the developing world where lack of facilities and
resources still results in diagnosis to be inferred mostly from the symptoms only. Reliable
and rapid diagnosis is urgently needed particularly in case of viral diseases with the concrete
risk of outbreaks going undetected in the early stages. In this article we will advocate the
necessity to implement robust point-of-care testing for viral diseases to overcome the
diagnostic gap of less developed countries.
.33
RE
ING
re
K
Introducing point-of-care testing
Point-of-care testing (POCT) is generally defined as medical testing at or near the site of patient care,
but encompasses a large variety of technologies for very different environments, which all have in
common a quick turnaround time between specimen collection and diagnosis [1,2] . On one side we
find very simple dipstick-based immunochromatographic (ICT) assays for self-testing, such as the
rapid HIV test kits that provide a result in less than 30 min from an oral swab [3] . On the other side
we find relatively sophisticated and expensive instruments that are used in hospitals for molecular
diagnosis that also require trained personnel for their use. Remaining on the HIV topic, confirmatory testing of seroconversion, measurement of viral load and CD4 + T cells’ count all require specific
complex laboratory instrumentation. The case of HIV infection is of particular interest because,
despite a very efficient specific combination antiretroviral therapy, the virus cannot be eradicated
[4] . Poor compliance of treatment leads inevitably to a relapse of viremia and the risk of selecting
resistant viruses. Hence, regular monitoring of HIV viral loads during combination antiretroviral
therapy is highly recommended and would enormously benefit from quick POCT. Between these two
extremes there is a wide range of rapid diagnostic tests that can be performed by minimally trained
health workers in the community. The global POCT market is expected to grow steadily in the next
years [5] . Manufacturers focus on the development of highly sensitive biosensors, less expensive optical systems, and noninvasive methods to be integrated into POCT devices for better performance.
Microfluidic systems based on the lab-on-chip (LOC) concept, along with improved biomarkers,
may witness a paradigm shift in the clinical diagnostics industry. But POCT has also the potential
to overcome the lack of a widely accessible health-care infrastructure in resource-limited settings.
As pointed out in a recent report from the American Academy of Microbiology, “in resource-limited
KEYWORDS
• developing countries
• lab-on-chip • LOC • POC
• POCT • point-of-care • viral
diagnosis
1
Department of Medical Laboratory Science, College of Medical Sciences, University of Maiduguri, P.M.B. 1069, Borno State, Nigeria
Laboratory of Molecular Virology, International Centre for Genetic Engineering & Biotechnology (ICGEB), Padriciano, 99 - 34149 Trieste,
Italy
*Author for correspondence: marcello@icgeb.org
2
10.2217/FVL.14.33 © 2014 Future Medicine Ltd
Future Virol. (2014) 9(6), 595–603
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settings, the impact of diagnostic tests that can be
provided at the immediate point-of-care (a POC
test) is potentially even greater, because the alternative to a POC testing may be no diagnostic support
at all” [6] . However, the development of POCT
diagnostics for the developing world should not
be a mere translation of a product developed for
other markets. Instead, POCT devices need to
be designed to perform in adverse local conditions of heat, humidity, dust, and possible lack of
infrastructures, running water or electricity being
operated by poorly experienced users. Finally,
even the best POCT device would be useless if
not linked to a program of treatment decisionmaking where the output of the assay is properly
managed locally and archived centrally.
In this review we will focus on the challenges
of translating POCT technology for viral disease
to resource-limited settings. To this end we will
take into consideration the most recent technology advances for virological testing and consider
the needs of a tertiary care health institution in
central Africa in order to provide a roadmap of
the actions to foster this challenging task.
Technologies of POCT
The ideal POCT has to adhere to a consensus of
features that go under the acronym ASSURED:
affordable, sensitive, specific, user friendly, rapid
and robust, equipment free (or minimal) and
deliverable to end users (WHO sexually transmitted diseases diagnostics initiative) [7] . Affordable
is a generic concept that depends only in part from
the cost of producing and marketing the device,
which varies a lot with the embedded technology applied and the scale of production. Also
relevant is the overall strategy of health policy
makers for funds allocation between centralized
laboratories or POCT technology to cover large
areas of their countries. Sensitivity and specificity
should be compared with their laboratory counterparts (i.e., ELISA for immunoassays and PCR
for molecular assays) to establish a suitable tradeoff for the increased numbers of patients being
tested. POCT devices should be simple enough
to be used by untrained users. Certainly, a striptest is a very simple technology that everyone can
apply and interpret. However, nowadays smartphone technology is so widespread that devices
operated in the same way are at the ease of most
of the world’s population. One note of caution
though, the ability to operate the device is only
one aspect of the problem since interpretation
and subsequent action should be in the hand of
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qualified healthcare workers that may decide to
refer the patient to a doctor for intervention. The
device should give a quick response (i.e., in minutes) and should be in a rugged format to resist in
a variety of extreme environments. All phases of
the procedure should be incorporated in a single
device: sample extraction (i.e., oral swab, urine
and blood) processing (i.e., extraction of nucleic
acids), testing (i.e., ICT or LOC/POCT) and
response (i.e., colorimetric and monitor display).
Finally, the device should be deliverable to end
users. This final concept includes most of the
recommendations above and is strictly dependent on the needs of those who will be using it.
A bottom–up approach is therefore highly recommended to drive the development of POCT
devices for resource-limited settings.
Lateral flow ICT devices for detection of antibody or antigen currently dominate POCT [8] .
These generally function like the pregnancy test
with the sample (urine, blood and saliva) diffusing by capillarity along a strip of porous material.
When the analyte (protein, antibody) reaches the
immobilized antigen/antibody, a colorimetric
reaction develops allowing the visual detection of
the signal. A positive control of test efficacy is also
included. The response of a strip test is usually
purely qualitative (yes/no), although it is possible
to measure the intensity of the test line to determine the quantity of analyte in the sample. These
kinds of test are also monoparametric, in that
they measure only one feature at a time. Finally,
recording of results is mostly not an automated
process requiring visual inspection and manual
annotation. There are several ICT assays for the
major viral diseases available on the market with
a variety of manufacturers. One great advantage
of these tests is that they can be easily produced
at a very low cost affordable to many developing
countries. However, a major hurdle is the high
heterogeneity and poor standardization of strip
tests making it very difficult to compare between
different studies [9] .
In the future, however, there will be an increasing need to develop cost-effective POCT devices
that address biomarkers, which may be well established in laboratory settings but are not currently
amenable to point-of-care, such as molecular
and/or multiparametric quantitative tests. The
LOC concept integrates one or several laboratory
functions on a single chip of only millimeters to
a few square centimeters in size. LOC applied to
POCT would deliver a complete package of diagnostic tests in a hand-held miniaturized format
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Virological point-of-care testing for the developing world
for easy handling and interpretation/storage of
output. Some of the advantages of a LOC/POCT
include: the handling of extremely small fluid
volumes (less reagents, lower costs of reagents,
less waste and less sample volumes required for
diagnostics); faster analysis and response times;
and lower fabrication costs from mass production. Furthermore, integration of LOC/POCT
with mobile smart phones, which are ubiquitously available and contain most of the components required for a biodetector (i.e., battery, display and processor), would allow availability and
accessibility of diagnostic testing also in developing countries exploiting a friendly technology [10] .
However, like for most innovative technologies
that are not yet fully developed, several hurdles
still need to be overcome. This is a fast developing field where a number of solutions are tested
but only a natural process of selection will tell
which technology will be the more robust and
cost effective for a specific LOC/POCT application. Integration of the different fields of immunology, molecular biology, chemistry, electronic
engineering, physics and material sciences is
required in a multidisciplinary approach for a
successful outcome.
Perhaps the most widely used laboratory
immunoassay technology is the ELISA, which
represents the standard for comparison against
all newly developed methods. The ELISA takes
advantage of the high affinity of the antibody–
antigen interaction and involves the immobilization of the antibody–antigen complex onto a
solid surface in a 96-wells format with enzymes
conjugated to antibodies being used to develop
a colorimetric reaction. Critical for the development of ELISA-based LOC/POCT is the
detection of the signal since the other steps of
the reaction are easily down scalable. However,
detection of the antibody–antigen binding cannot be obtained by the classical colorimetric
reaction therefore requiring alternative technologies. Electrochemical and optical immunosensors are being developed for this purpose [11] . A
very promising cost-effective optical technology
for the development of LOC/POCT is based on
organic light-emitting diodes (OLED): flat, few
millimeters thick surfaces that can be designed
to emit light in different wavelengths [12–17] .
The molecular architecture and emission spectrum of the OLED can be optimized to match
the excitation spectrum of a fluorophore used
in the detection reaction. The signal is captured by a detector and processed in real time
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allowing a wide range of applications. Recently,
an immunoassay has been developed based on a
bottom-emission small molecule-based OLED
optimized to obtain the deep-blue wavelength
that is required to excite a succimide-based dye
conjugated to an antibody [18] . This configuration is currently being tested for the detection of immunoglobulins in sera from patients
infected with Flaviviruses such as Dengue virus,
tick-borne encephalitis virus and west Nile virus
(WNV) [Marcello A et al., Unpublished Data] .
Molecular techniques for the detection of
viral pathogens aim at the detection of the viral
nucleic acid, which can be RNA or DNA, circulating in the patient (viral load). Two levels
of output should be considered: the presence
of the pathogen/nucleic acid (qualitative) and
the amount of pathogen/nucleic acid (quantitative). The latter is of paramount importance,
for example, in the HIV field because, together
with other critical parameters such as the CD4 +
T-cell counts and clinical symptoms, determines
the progression towards AIDS. Direct detection
by nucleic acid hybridization can be achieved but
levels of circulating viruses may be low therefore
usually requiring an amplification step to gain
in sensitivity. Nucleic acid amplification may
be obtained by isothermal amplification or by
PCR, which requires several thermal cycles of
amplification/denaturation/annealing. While
the latter is a challenge for engineers due to the
large delta of temperatures required for the reaction, it still remains the most robust technique
for viral nucleic acid detection while awaiting
further development of the former [19] . Indeed,
preliminary studies have shown that in principle it is possible to detect a viral nucleic acid by
acquiring in real-time a fluorescent signal from
PCR conducted directly on an emitting light
surface [Marcello A et al., Unpublished Data] [20] .
Paradoxically however, a field-tested portable
PCR system that summarizes all the features
of a LOC/POCT for developing countries has
been originally conceived for military use. The
RAZOR EX BioDetection System (RAZOR;
BioFire Diagnostics, UT, USA [formerly Idaho
Technologies, recently acquired by BioMerieux])
employs real-time PCR technology to identify
biological pathogens taking advantage of system-integrated freeze-dried reagents packaged
in durable plastic pouches. RAZOR has been
designed specifically for field use with compact
and lightweight design (size: 25.4 × 11.4 × 19
cm; weight: 4.9 kg including batteries). The
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device can simultaneously test up to ten pathogens with results available in less than 30 min.
Originally developed for first responders and
front-line military troops, it is easily operated
while working in protective equipment under
extreme conditions. Further developments in
the direction of better integrating DNA/RNA
extraction, PCR and real-time detection in a
single easy-to-use instrument are underway.
POCT for viral diseases
The importance of virological POCT for industrialized countries is restricted to conditions
that require a rapid turnaround time since most
routine testing is performed in well-distributed
diagnostic laboratories serving the community.
For example, results from conventional HIV
serology take between 30 min to a few hours or
even days in a busy laboratory while POCT takes
as little as 10 min. This turnaround time can
be critical since it has been estimated that 30%
of HIV-positive individuals and 39% of HIVnegative individuals testing at publicly funded
counseling/testing/referral programs do not
return for their test results [CDC, Unpublished Data] .
Therefore, these individuals cannot receive counseling about medical treatment and behavioral
risks. Use of a POCT with immediate results
substantially increases the number of people
who know their HIV status and receive information about next steps. Aside from HIV infections, respiratory infections can lead to severe
complications if viruses such as the respiratory
syncytial virus or influenza virus are involved.
Rapid immunoassays for these pathogens can be
run in an emergency department or clinic in 15
min. Since flu-like symptoms are also typical of
many other endemic diseases, quick and accurate diagnosis is important to direct the optimal
treatment and to avoid inappropriate antibiotic or antimalaria prescription [21] . The same
concept applies to the detection of enterovirus
RNA in cerebrospinal fluid for the differential
diagnosis of meningitis [22] . The importance of
rapid POCT in emerging infectious disease is
also reinforced by the recent outbreak of several new pathogens, including West Nile virus
in the Americas and the Coronavirus SARS
(severe acquired respiratory syndrome outbreak
2002–2003) and MERS (Middle East respiratory syndrome outbreak 2012–2013). The quick
spread of SARS from Asia to North America
already demonstrated how critical rapid on-thespot diagnosis and treatment decisions could be
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with regards to disease containment efforts highlighting the importance of being prepared for
rapid action to counter the spread of previously
unknown agents or known infectious agents that
are re-emerging or used as bioweapons.
The spectrum of viral infections that could
benefit from POCT in the developing world is
much wider. Lack of resources and widespread
healthcare facilities make immense areas of the
world completely uncovered from viral detection. This has severe implications at various
levels. First, quick response to viral outbreaks
would limit the number of cases of life-threatening diseases such as hemorrhagic fevers from
Ebola virus and Lassa virus. Second, a better
diagnosis of the etiological agent responsible for
generic symptoms like fever or diarrhea would
limit the misuse of improper treatments. Third,
the more an emerging or re-emerging viral infection remains undetected the less it is likely to
be contained avoiding a worldwide pandemic.
Hence, the benefit of POCT testing in the developing world goes well beyond the interests of
the people directly involved at the outbreak site.
POCT for major diseases are available in ICT
format for the detection of reactive immunoglobulins in patients’ sera (IgM/IgG). However,
a combination of tests is generally required for a
complete diagnosis of a single disease, as well as
for the coverage of all the possible/most probable causes of a symptomatic state. This is why
multiparametric LOC/POCT tests represent the
ultimate frontier of delocalized viral diagnostics. But what would be the kind of test that is
required? This would depend from the pathogen
and the various phases of the disease. A paradigmatic example is Dengue virus (DENV). With
more than a third of the world’s population living in areas at risk of infection, DENV is a leading cause of illness and death in the tropics and
subtropics [23] . As many as 400 million people
are infected yearly with symptoms of increased
morbidity: Dengue fever, dengue hemorrhagic
fever and Dengue shock syndrome. DENV
belongs to the Flavivirus genus of the family
Flaviviridae that include also hepatitis C virus
(genus: Hepacivirus). Members of the Flavivirus
are arthropod-borne viruses (Arboviruses) that
include other important human pathogens
such as yellow fever virus (YFV), WNV and
tick-borne encephalitis virus. There are four distinct serotypes of DENV1–4, which all cause
clinical disease. Understanding the dynamics
of DENV infection is critical because it has
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Virological point-of-care testing for the developing world
a large impact on the interpretation of diagnostic results. Following the initial infection,
DENV replicates to high titers in the blood
before patients are unwell enough to present to
a physician, with viremia peaking at the time
or shortly after the onset of symptoms. During
the viremic phase of dengue infection a soluble form of the nonstructural viral protein NS1
circulates in the serum of patients and hence is
an excellent diagnostic target for acute Dengue
together with the detection of viral RNA and
DENV isolation. Dengue IgM antibody is
a reliable marker of recent infection but not
necessarily acute infection. In primary DENV
infections, IgM antibodies develop following the
decline of viremia between days 3–5 after the
onset of infection and persist for approximately
6 months. However, amplitude and duration of
the IgM during secondary infections, that are
most common among individuals with previous
Flavivirus infections or immunizations against
these viruses, are smaller and shorter. The IgG
antibody response, which develops a few days
after the onset of the IgM antibody response, is
serotype specific and may persist for many years
following a single infection. During secondary
infections the IgG response is before the IgM
response or simultaneous. Several ICT tests are
available for IgM/IgG detection and a great
effort has been put in the improvement of their
specificity and sensitivity [24] . However, the most
important development in Dengue diagnostics
in recent years has been the specific detection
of the DENV NS1 antigen. ICT for NS1 and
IgM/IgG allows the rapid differential determination of acute versus recent or past DENV
infection thus greatly improving diagnosis.
ICT tests for DENV suffer from the same
problems of their ELISA counterparts for specificity and sensitivity. Flaviviruses are antigenically related and all immuno-based tests show
a certain degree of crossreactivity particularly
in areas where different members of the genus
and/or family are co-existing [25] . Furthermore,
differential diagnosis of the four serotypes of
DENV would be also important particularly in
areas experiencing a shift from one serotype to
another. The phenomenon of antibody-dependent enhancement occurs when non-neutralizing
antibodies from a previous infection of a particular serotype facilitate entry of the second DENV
of a different serotype into the host cells, leading to increased infectivity [26] . In such cases,
the clinical course of the disease is more severe
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with higher viremia and increased risk of dengue hemorrhagic fever/Dengue shock syndrome.
The golden standard for differentiating viral serotypes is the plaque-reduction neutralization test
that measures viral infectivity in the presence
of patients’ neutralizing sera [27] . However, its
implementation is cumbersome, may last several
days (6–10 days depending on the serotype) and
requires expert virologists in a containment laboratory. Semiautomated methods are being developed to shorten plaque-reduction neutralization
test and making it less operator sensitive but their
implementation to POCT appears less likely in
the short term [28] . In summary, for Dengue it
would require merging in a single test IgM/IgG
detection with NS1 or viral RNA. Multiplexing
these assays together with their counterparts for
a panel of arboviruses that could be responsible
for malaria/typhoid-negative febrile symptoms
could represent a valid tool in endemic areas as
described below.
Challenges & solutions for POCT in
resources-limited settings
Nigeria is the most populous country in Africa
with a population exceeding 170 million. The
burden of viral diseases in the country is enormous with an estimated 3.3 million living with
HIV/AIDS. Few data are available on other viral
diseases that could date back several decades with
only few more recent systematic reports. Dengue
virus was first isolated in the sixties [29,30] and
presently seems the leading arbovirus in the country, followed by Yellow fever virus, Chikungunya
and West Nile virus [31,32] . Another example is a
recent measles outbreak, which caused 36,428
cases and 198 deaths (reported by Medecins Sans
Frontiers in 2013) [33] . In the case of rabies, an
estimated 10,000 people, mostly children, are
exposed to dog bites each year but the burden of
the disease is largely underestimated, as it is for
most diseases that get underdiagnosed and underreported due to lack of diagnostic facilities and
trained personnel. Finally, Nigeria is also one of
the few polio-endemic countries left worldwide,
with 53 confirmed poliomyelitis cases in 2013,
notwithstanding the global polio eradication vaccine initiative promoted by the WHO (Global
Polio Eradication Initiative 2014) [34] .
The University of Maiduguri Teaching
Hospital (UMTH, Maiduguri, Nigeria) is a
tertiary health institution that serves as a referral health center for six states in north eastern
Nigeria (Borno, Taraba, Adamawa, Yobe, Gombe
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REVIEW Baba, Vidergar & Marcello
and Bauchi), and neighboring African countries
(Chad to the North East, Niger to the North and
Cameroon to the East). The institution also hosts
one of the two WHO National Polio Laboratories
that is part of the polio eradication program [35] .
A limited number of viral diseases are being diagnosed at UMTH. Serological procedures such as
ELISA or rapid strip tests are used together with
virus isolation in cell culture and neutralization
assays. Recently, the introduction of real-time
PCR allowed molecular detection to take place.
However, the high cost of the equipment and
reagents, as well as the need for skilled/qualified
operators heavily limits its use.
UMTH is a paradigmatic example of the
challenges of viral diagnosis in Africa. Malaria,
for example is usually ascribed to all febrile illnesses unless confirmed through laboratory
testing. Febrile patients regularly exhibit symptoms, which are generally believed to be caused
by malaria or typhoid, but that are also commonly observed with arbovirus infections. It is
a common practice for patients with fever to
visit the healthcare facility only if fever persists
after self-medication with two or three different
antimalaria treatments. At this stage it becomes
very difficult to isolate or detect the virus by
reverse transcriptase PCR. The use of serology
in such cases would be appropriate, but high levels of crossreactivity among these viruses make
their differentiation equally difficult. In a pilot
study, a total of 310 blood samples were collected
from patients exhibiting febrile illness who visited the UMTH. Microscopy screening for the
malaria parasite, Widal agglutination reaction
for Salmonella Typhi infection and neutralization
assays for WNV, YFV, DENV 1–4 and CHKV
were used [36] . The results were stunning: of the
310 febrile sera samples tested here, 285 (92%)
tested positive for malaria, typhoid and arbovirus infection, or a combination of one or more
of these viruses (Figure 1) . Interestingly, 25 (8%)
of the 310 patient sera tested were negative for
all six pathogens suggesting that other pathogens may also be circulating, possibly including
arboviruses such as O’nyong nyong, Bwamba,
Tataguine, Thogoto, Wesselsbron, CrimenanCongo hemorrhagic fever, Zika, Lassa or Dugbe
[37–40] .
Despite the enormous hurdles for viral diagnosis in Africa, there are examples where POCT is
being introduced. Recent approaches propose the
use of a portable isothermal reverse transcription
recombinase polymerase amplification (RT-RPA)
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assay for the detection of viral RNA [41] . This
rapid (15 min) and sensitive technology entails
the amplification of cDNA at temperatures of
25–42°C and fluorescence detection of the signal in real time in the ESEQuant tubescanner
(Qiagen, Hilden, Germany). This device is portable (weights ∼1 kg) and can be powered by a
car adaptor or by batteries rechargeable by solar
panels, making it very suitable for resource-limited settings. A mobile RT-RPA unit was set up
during a foot-and-mouth disease virus outbreak
in Egypt in 2012, allowing for the first successful field test performed directly at the quarantine stations. The control of infected livestock is
of paramount importance for the management
of FMD outbreaks that cause huge economic
losses. However, the technology applies also
for human disease as it has been demonstrated
for the MERS-CoV and YFV [42,43] . The latter
study was conducted in Senegal and included also
steps towards the integration of the RT-RPA into
a semiautomated LOC/POCT system using a
microfluidic cartridge and a small and portable
processing device that could be used in the field
with minimal manual interaction.
Conclusion
The number of POCT devices available to detect
viral infections is steadily increasing. Although
the majority of them worldwide are ICT based,
more complex LOC/POCT tests are also being
proposed. However, the capillary availability of
centralized laboratories in more advanced countries limits the development of POCT for viral
infections because of their lower levels of sensitivity and specificity that cannot compete with the
high standards of laboratory-based tests. On the
other hand, in resource-limited settings, where
laboratory testing is lacking or underperforming,
the POCT device could represent a convenient
trade-off. This opportunity cannot be missed to
reduce the burden of disease in those countries
where it is more urgent. In order to accelerate the
process from the initial design of a POCT to its
implementation in developing countries, transversal partnerships should be formed between
academic researchers, international organizations
and healthcare institutions. Only by involving all
the relevant stakeholders we shall move forward
in the diagnostic of infectious disease in resourcelimited countries. It is envisaged that availability of appropriate diagnostic tests will not only
improve virus surveillance but also reduce costs
of inappropriate treatment. Furthermore, they
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DENV1-4
95
WNV
11
11
31
59
0
0
0
1
3
15
CHIKV
25
DENV1-4 + YFV = 0
6
YFV
WNV + CHIKV = 15
Figure 1. Seroprevalence of arbovirus infection at the University of Maiduguri Teaching
Hospital (Maiduguri, Nigeria). In total, 310 human sera were tested for DENV1–4, WNV, YFV, CHIKV,
Plasmodium falciparum and Salmonella Typhi. A total of 272 tested positive for one or more arbovirus
while two tested positive for malaria alone, 11 for S. Typhi alone, none for both and 25 were negative
for all pathogens tested.
CHIKV: Chikungunya; DENV: Dengue virus; WNV: West Nile virus; YFV: Yellow fever virus.
Data taken from [36].
will reduce under-reporting and overdiagnosis
of these diseases (i.e., malaria in febrile illness)
in endemic countries and consequently decrease
the potential of uncontrolled spread of enzootic
viruses that have recently been rising serious
public health concerns. Thinking that this not a
problem for developed countries is a dangerous
underestimation of the risk for future pandemics.
When it comes to infectious diseases no country
is an island and everyone would benefit from a
better monitoring of the periphery of the world.
Future perspective
Development of innovative and affordable portable diagnostic assays for developing countries is
the most promising way to reduce the turnaround
future science group
time between disease manifestation and treatment, thus minimizing disease transmission and
impact. In the future, we will experience the reinforcement of ICT-based technologies and a technological shift to LOC/POCT multiparametric
quantitative interconnected devices.
Therefore, strategies should be put in place to
implement ICT-based testing for the detection
of acute/recent viral infections, standardize ICTbased testing with international guidelines and
develop novel LOC/POCT devices that may represent the future of diagnosis in resource-limited
settings.
Ultimately, LOC/POCT devices should be
able to perform a multiparametric analysis, combining both serology and molecular detection of
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REVIEW Baba, Vidergar & Marcello
viral nucleic acids and/or proteins. These can be
directed towards a single pathogen (i.e., Dengue
virus) or towards a panel of pathogens with similar symptoms (i.e., respiratory disease and febrile
illness).
Acknowledgements
The authors would like to thank G Corazza for reading the
manuscript.
Financial & competing interests disclosure
M Baba was funded by an ICGEB short-term fellowship
programme grant (F/NIG08-5) and a Volkswagen Stiftung
‘Knowledge for tomorrow: Cooperative Research in SubSaharan Africa’ travel grant (24112008). Virological testing at UMTH has been implemented thanks to collaboration with ICGEB, the Bernhard-Nocht-Institute for
Tropical Medicine (S Günther) and the ‘Burlo Garofolo’
Hospital in Trieste, Italy (P D’Agaro). N Vidergar is financially supported by OREL.doo. A Marcello is a consultant
of OREL.doo for the development of OLED-based devices.
His work on LOC/POCT has been funded by: the National
R&D project ‘DIA OLED’ financed by Regione Friuli
Venezia Giulia of Italy (art. 12, DM 593/2000), in collaboration with Plast-Optica Spa, Eurotech Spa, Euroclone
Spa, Alphagenics Srl and University of Trieste; the
International R&D Project ‘OLED CHIP’ financed by
FP7 ER A NET in collaboration with OREL.doo
(Slovenija), Cosylab (Slovenija), Laplace-CNRS (France),
LED Engineering (France); the POR-FESR Project
‘FLAVIPOC’ financed by Regione Friuli Venezia Giulia
of Italy in collaboration with Euroclone Spa, University of
Trieste, Hospital Burlo Garofolo and Cluster of
Biomedicine. The authors have no other relevant affiliations or financial involvement with any organization or
entity with a financial interest in or financial conflict with
the subject matter or materials discussed in the manuscript
apart from those disclosed.
No writing assistance was utilized in the production of
this manuscript.
EXECUTIVE SUMMARY
Point-of-care testing for viral infections encompass a variety of techniques
●
Immunochromatographic-based assays are simple, cheap and dominate the ield but are monoparametric and mostly
not quantitative.
●
Lab-on-chip (LOC)/point-of-care testing (POCT) are still in the development phase but represent the future of
multiparametric quantitative analysis.
POCT is the most feasible solution to overcome the diagnostic gap of resource-limited countries
●
Lack of a capillary distribution of diagnostic laboratories does not allow early diagnosis and viral outbreak detection in
resource-limited countries.
●
The implementation of portable diagnostic devices that can be operated with minimal knowledge by healthcare
workers represent a valid alternative to the construction of permanent infrastructures.
●
There is a window of opportunity to develop POCT speciically for the need of the less developed countries.
●
POCT for resource-limited settings should carefully take into account the necessities of the end user in a bottom–up
collaborative approach.
Future perspective
●
ICT-based assays need to be reinforced and standardized.
●
LOC/POCT assays for viral infections should be further implemented.
●
Immunological and molecular techniques may be combined to provide LOC/POCT formats for the detection of
multiple pathogens or multiple parameters of a single infection to guide intervention.
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