Diarrheal Diseases

This essay contains two hypotheses: the first postulates that infectious and parasitic conditions in the first baby-carrying devices or “slings” selected for changes in juvenile hair distribution and immuno-resistance, and that a convergence of datable mutations and osteological changes indicate that infants in our lineage adapted to the microenvironment between 1.2 and 2.8 million years ago - with evidence converging towards the older end of that range. Such slings, which might have been first used to carry gleanings, would have surrounded offspring in dangerous pathogens and parasites. Babies whose fetal body baldness had not disappeared would have had an advantage over infants with previously normal body fur, because adults could clean them better – probably resulting in the neotenic extension of the fetal trait.
The microenvironment might have selected for the elimination of infectious pathways as well. The inactivation of the CMAH gene, which could have provided a pathway for pathogens associated with ungulate and proboscidean hides to infect infants with diarrhea, is explored as a candidate, and multiple ways of testing the hypothesis are described.
The related hypothesis, which is based partly on avian comparisons and milk chemistry, postulates that slings gradually forced adults to focus on the kind of nutrition needed by more slowly maturing infant brains by making their babies more altricial. This might have triggered more scavenging, hunting, and feedback mechanisms that slowly extended the new juvenile hair distribution to adults as part of a whole-body cooling system based on sweat and body baldness while contributing to speciation.

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BACKGROUND:
The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC(-)ssaV(-)) ZH9 with two independently attenuating deletions. Studies in healthy adults demonstrated immunogenicity and an acceptable safety profile.
OBJECTIVES:
We conducted a randomised placebo controlled, single-blind trial to evaluate the safety and immunogenicity of M01ZH09 in healthy Vietnamese children aged 5 to 14 years.
METHODS:
Subjects were randomly assigned to receive either a nominal dose of 5x10(9) CFU of M01ZH09 or placebo and were followed up for 28 days. The primary safety outcome was the proportion of subjects with any adverse event attributed to M01ZH09. The primary immunogenicity endpoint was the proportion of subjects who showed a positive immune response to M01ZH09 in the Salmonella Typhi lipopolysaccharide (LPS) specific serum IgA and IgG ELISA.
PRINCIPAL FINDINGS:
One hundred and fifty-one children were enrolled, 101 subjects received M01ZH09 and 50 subjects received placebo. An intention to treat analysis was conducted. There were no serious adverse events and no bacteraemias. In the M01ZH09 group, 26 (26%; 95% CI, 18-5%) of 101 subjects experienced adverse events compared to 11 (22%; 95% CI, 12-36%) of 50 subjects in the placebo group (odds ratio (OR) [95%CI] = 1.23 [0.550-2.747]; p = 0.691). Faecal shedding of S. Typhi (Ty2 aroC(-)ssaV(-)) ZH9 was detected in 51 (51%; 95% CI, 41-61%) of 100 M01ZH09 subjects. No shedding was detected beyond day 3. A positive immune response, defined as 70% increase (1.7 fold change) in LPS specific serum IgG (day 14 or 28) and/or 50% increase (1.5 fold change) in LPS specific serum IgA (day 7 or 14) from baseline was detected in 98 (97%; 95% CI, 92-99%) of 101 M01ZH09 recipients and 8 (16%; 95% CI, 7-29%) of 50 placebo recipients. Twenty-eight (100%; 95% CI, 88-100%) of 28 vaccine recipients who were evaluated in the LPS specific IgA ELISPOT assay showed a positive response compared to none of the 14 placebo recipients tested.
CONCLUSIONS:
This was the first phase II trial of a novel oral candidate typhoid vaccine in children in an endemic country. M01ZH09 had an appropriate safety profile and was immunogenic in children.
TRIAL REGISTRATION:
Controlled-trials.com ISRCTN91111837.

During diarrhea, a patient will have a frequent abnormal passage of loose, liquid or watery stools and causes depletion of body fluids, resulting in profound dehydration. Acute diarrhea refers to the episodes of infectious diarrhea, which have a rapid onset and lasts for about 3 to 7 days but may last up to 10 to 14 days. When two or more people in a community or geographical area have a similar illness or proven infection due to common exposure then it is termed as an outbreak. Variations in weather and climate conditions will influence the intensity of disease outbreaks and thus understanding the influence of the seasons on the infectious disease outbreaks is very important for public health monitoring. The objective of this study is to understand the seasonal variations of the acute diarrheal disease (ADD) outbreaks in India. We analyzed the weekly ADD outbreaks data from 2010 till 2018 that is published as a part of the Integrated Disease Surveillance Programme by National Centre for Disease Control, Directorate General of Health Services. The results of the analysis show that in India, ADD outbreaks will be more during the month of May (peak summer) but predominantly maximum during the month of July (when monsoon prevails).

Hemocytes of the Asian freshwater clam Corbicula fluminea, phagocytosed in vitro infectious Giardia duodenalis cysts. After 15, 30, 60, 90, and 120 min of incubation an average of 22%, 32%, 43%, 54%, and 72% of the cysts were phagocytosed by 22%, 55%, 63%, 81%, and 86% of the hemocytes, respectively. The number of hemocytes showing phagocytosis and the mean number of cysts ingested per hemocyte increased␣significantly over time (P < 0.01); the numbers of nonphagocytosed cysts significantly decreased (P < 0.02). Extrapolation reveals that C. fluminea can retain by phagocytosis an average of 1.6 × 106G. duodenalis cysts/ml hemolymph. The phagocytic capacity of C. fluminea hemocytes indicates the applicability of this freshwater benthic bivalve for bioindication of contamination of waste waters and agricultural drainage with Giardia cysts.

In a prospective study carried out among Jordanian children in Amman, a total of 73/250 (29.2%) stool specimens were positive for 1 or more diarrhoeagenic Escherichia coli strains using a multiplex polymerase chain reaction method. This study indicated that diarrhoeagenic E. coli isolates were found frequently more in stools of children with diarrhoea (34%) than without diarrhoea (23.1%), but without any significant difference (p
/0.05). The predominant diarrhoeagenic E. coli strains associated with diarrhoea were enteropathogenic E. coli (11.3%), followed by enterotoxigenic E. coli (9.8%) and enteroaggrative E. coli (9%), whereas in the control group these were 4.3%, 11.1% and 6%, respectively. Enteroinvasive E. coli strains (2.9%) were found only in stools of children with diarrhoea. This study revealed the absence of enterohaemorrhagic E. coli in both diarrhoeal and control stools, and found that diarrhoeagenic E. coli isolates were highly resistance to tetracycline (55%), co-trimoxazole (60%) andampicillin (89%), which are commonly used antibiotics in Jordan.

This paper has reviewed researches that obtained from peer-reviewed literatures on Salmonellosis and Shigellosis. Foodborne diseases related to unhygienic food handling practices remain a major public health problem across the globe. The problem is severe in developing countries due to limitations in securing optimal hygienic food handling practices. Data shows that an estimated 70 % of cases of diarrheal diseases are associated with the consumption of foods contaminated with pathogenic microorganisms. Among these microorganisms Salmonella and Shigella are the major ones. In this review, it is noted that these potentially pathogens are still public health problems. Therefore, there needs to be frequent monitory and evaluation system so as to plan intervention strategies for at risk population in the area of water sanitation and hygienic food handling practice to minimize the burden posed by the diseases associated with Salmonellosis and Shigellosis.