Changing patient population in Dhaka Hospital and Matlab Hospital of icddr,b

Epidemiological characteristics and transmissibility of shigellosis in Hubei Province, China, 2005 - 2017

BACKGROUND

Shigellosis is one of the main diarrhea diseases in developing countries. However, the transmissibility of shigellosis remains unclear.

METHODS

We used the dataset of shigellosis cases reported between January 2005 and December 2017, from Hubei Province, China. A mathematical model was developed based on the natural history and the transmission mechanism of the disease. By fitting the data using the model, transmission relative rate from person to person (b) and from reservoir to person (bw), and the effective reproduction number (Reff) were estimated. To simulate the contribution of b and bw during the transmission, we performed a "knock-out" simulation in four scenarios: A) b = 0 and bw = 0; B) b = 0; C) bw = 0; D) control (no intervention).

RESULTS

A total of 130,770 shigellosis cases were reported in Hubei province, among which 13 cases were dead. The median annual incidence was 19.96 per 100,000 persons (range: 5.99 per 100,000 persons - 29.47 per 100,000 persons) with a decreased trend (trend χ2 = 25,470.27, P < 0.001). The mean values of b and bw were 0.0898 (95% confidence interval [CI]: 0.0851-0.0946) and 1.1264 × 10- 9 (95% CI: 4.1123 × 10- 10-1.8416 × 10- 9), respectively. The "knock-out" simulation showed that the number of cases simulated by scenario A was almost the same as scenario B, and scenario C was almost the same as scenario D. The mean value of Reff of shigellosis was 1.19 (95% CI: 1.13-1.25) and decreased slightly with a Linear model until it decreased to an epidemic threshold of 0.99 (95% CI: 0.65-1.34) in 2029.

CONCLUSIONS

The incidence of shigellosis is still in high level. The transmissibility of the disease is low in Hubei Province. The transmission would be interrupted in the year of 2029.

Bangladesh: a success case in combating childhood diarrhoea

BACKGROUND

Bangladesh had a large reduction in childhood deaths due to diarrhoeal disease in recent decades. This paper explores the preventive, promotive, curative and contextual drivers that helped Bangladesh achieve this exemplary success.

METHODS

Primary and secondary data collection approaches were used to document trends in reduction of Diarrhoea Specific Mortality Rate (DSMR) between 1980 and 2015, understand what policies and programmes played key roles, and estimate the contribution of specific interventions that were implemented during the period. Data acquisition involved relevant document reviews and in-depth interviews with key stake-holders. A systematic search of literature was undertaken to explore socio-economic, aetiological, behavioural, and nutritional drivers of diarrhoeal disease reduction in Bangladesh. Finally, we used LiST (Lives Saved Tool) to model the contributions of the relevant interventions during three time periods (1980-2015, 1980-2000 and 2000-2015), and to project the number of lives saved in 2030 (compared to 2015) if these interventions were implemented at near universal coverage (90%).

RESULTS

The factors which likely had the most impact on DSMR were the coordinated efforts of the Government of Bangladesh (GoB) with non-government organizations (NGOs) and the private sector that enabled swift implementation, at scale, of interventions like oral rehydration solution (ORS) and zinc, promotion of breastfeeding, handwashing and sanitary latrines (WASH), as well as improvements in female education and nutrition. Compared to 1980, we found ORS and reduction in stunting prevalence had the greatest impact on DSMR, saving roughly 70 000 lives combined in 2015. Until 2000, ORS had a higher contribution to DSMR reduction than reduction in stunting prevalence. This proportionate contribution was reversed during 2000-2015. At near universal coverage (90%) of combined direct diarrhoeal disease, nutrition and WASH interventions, we project that an additional 5356 deaths due to diarrhoea could be averted in 2030.

CONCLUSION

Bangladesh's achievement in reduction of DSMR highlights the important role of an enabling policy environment that fostered coordinated efforts of the public and private sectors and NGOs for maximal impact. To maintain this momentum, evidence-based interventions should be scaled up at universal coverage.

Cholera in selected countries in Asia

INTRODUCTION

Although the current pandemic of cholera originated in Asia, reports of cholera cases and outbreaks in the region are sparse. To provide a sub-regional assessment of cholera in South and Southeast Asia, we collated published and unpublished data from existing surveillance systems from Bangladesh, Cambodia, India, Malaysia, Nepal, Pakistan, Philippines, Thailand and Vietnam.

METHODS

Data from existing country surveillance systems on diarrhea, acute watery diarrhea, suspected cholera and/or confirmed cholera in nine selected Asian countries (Bangladesh, Cambodia, India, Malaysia, Nepal, Pakistan, Philippines, Thailand and Vietnam) from 2011 to 2015 (or 2016, when available) were collated. We reviewed annual cholera reports from WHO and searched PubMed and/or ProMED to complement data, where information is not completely available.

RESULTS

From 2011 to 2016, confirmed cholera cases were identified in at least one year of the 5- or 6-year period in the countries included. Surveillance for cholera exists in most countries, but cases are not always reported. India reported the most number of confirmed cases with a mean of 5964 cases annually. The mean number of cases per year in the Philippines, Pakistan, Bangladesh, Malaysia, Nepal and Thailand were 760, 592, 285, 264, 148 and 88, respectively. Cambodia and Vietnam reported 51 and 3 confirmed cholera cases in 2011, with no subsequent reported cases.

DISCUSSION AND CONCLUSION

We present consolidated results of available surveillance in nine Asian countries and supplemented these with publication searches. There is paucity of readily accessible data on cholera in these countries. We highlight the continuing existence of the disease even in areas with improved sanitation and access to safe drinking water. Continued vigilance and improved surveillance in countries should be strongly encouraged.

Renal insufficiency among urban populations in Bangladesh: A decade of laboratory-based observations

OBJECTIVE

The objective of this study was to describe the age and sex-specific prevalence of renal insufficiency, and observe its trends over a decade at an urban Bangladesh setup.

METHOD

This was a cross-sectional study, in which we observed the Estimated Glomerular Filtration Rate (eGFR) of 218,888 adults, aged ≥19 years, who had submitted their blood specimen to the Clinical Biochemistry Laboratory of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) during the years 2006-2015. We applied CKD-EPI definition in estimating eGFR using their age-and sex-specific serum creatinine concentrations. Based on the eGFR, we classified the population into five stages of renal insufficiency (stage-1 to stage-5), at age intervals of five-years. Data were analysed using the Linear Regression and Multinomial Logistic Regression models.

RESULTS

Females constituted 43% (n = 94,931) of the study population; and 34% (n = 42,576) of the males and 31% (n = 29,830) of the females had their serum creatinine concentrations above the upper limit of the laboratory reference cut-off. The overall prevalence of stage-2 to stage-5 renal insufficiency were 24% (n = 52,126), 17% (n = 38,539), 8% (n = 16,504) and 6% (n = 12,665) respectively; the prevalence were 23% (n = 1,890), 19% (n = 1,579), 9% (n = 769) and 9% (n = 770) respectively in 2006, and 24% (n = 10,062), 17% (n = 6,903), 6% (n = 2,537) and 5% (n = 1,924) respectively in 2015. The prevalence was higher among the females. At least 2% of the adults, younger than <44 years, had stage-4 and stage-5 in 2015. The age-adjusted eGFR was significantly lower among the post-menopausal females (aged ≥46 y) compared to the same age group males (64.08±10.83 vs. 66.83±10.41 mL/min/1.73 m2; p<0.001). Compared to 2006, the number of individuals with renal insufficiency (stage 2 and above) had increased at least two times, irrespective of age, in 2015. A single year of increase in the age was significantly associated with 1.32 unit reductions in the eGFR; and the reductions were higher for females who also had higher odds of renal insufficiency stages-2 and beyond.

CONCLUSION

This study observed high prevalence of stage-2 to stage-5 renal insufficiency in Bangladeshi populations, irrespective of age, and especially among the females.

IncA/C plasmids conferring high azithromycin resistance in vibrio cholerae

Azithromycin (AZM) is a clinically important antibiotic against Vibrio cholerae, especially for inhibiting V. cholerae colonisation of the intestine and for the treatment of severe cholera in children and pregnant women. An IncA/C plasmid was isolated from two high minimum inhibitory concentration (MIC) AZM-resistant V. cholerae strains of the two mainly pathogenic serogroups (O1 and O139) isolated in China. In the 172 predicted open reading frames (ORFs), 16 genes were related to antibiotic resistance, of which 5 were well-defined genes associated with macrolide resistance. The five macrolide resistance genes distributed in two clusters, mphR-mrx-mph(K) and mel-mph2, flanked by insertion sequence elements and involving two kinds of resistance mechanism. Deletion of the complete region of the two clusters deceased the AZM MIC from ≥64 µg/mL to ≤0.5 µg/mL. This IncA/C plasmid shows great ability to accumulate antibiotic resistance genes. In addition to 11 resistance genes to other antibiotics, 5 macrolide resistance genes with different function were gathered repeatedly through transposition on one plasmid. This genotype could not be simply explained by antibiotic stress applied on the host from the environment or treatment. These phosphorylases and transmembrane transporters might be involved in the transport and metabolism of other non-antibiotic substances, enabling this kind of plasmid to propagate better in the host.

Shigellosis: Epidemiology in India

Shigellosis is one of the major causes of diarrhoea in India. The accurate estimates of morbidity and mortality due to shigellosis are lacking, though it is endemic in the country and has been reported to cause many outbreaks. The limited information available indicates Shigella to be an important food-borne pathogen in India. S. flexneri is the most common species, S. sonnei and non-agglutinable shigellae seem to be steadily surfacing, while S. dysenteriae has temporarily disappeared from the northern and eastern regions. Antibiotic-resistant strains of different Shigella species and serotypes have emerged all over the world. Especially important is the global emergence of multidrug resistant shigellae, notably the increasing resistance to third generation cephalosporins and fluoroquinolones, and also azithromycin. This calls for a continuous and strong surveillance of antibiotic resistance across the country for periodic updation of the local antibiograms. The prevention of shigellosis is desirable as it will substantially reduce the morbidity associated with diarrhoea in the country. Public health measures like provision of safe water and adequate sanitation are of immense importance to reduce the burden of shigellosis, however, the provision of resources to develop such an infrastructure in India is a complex issue and will take time to resolve. Thus, the scientific thrust should be focused towards development of a safe and affordable multivalent vaccine. This review is focused upon the epidemiology, disease burden and the therapeutic challenges of shigellosis in Indian perspective.

Antibiotic resistance and plasmid profiling of Vibrio spp. in tropical waters of Peninsular Malaysia

Vibrio species isolated from four different sampling stations in the west coast of Peninsular Malaysia were screened for their antimicrobial resistance and plasmid profiles. A total of 138 isolates belonging to 15 different species were identified. Vibrio campbellii, V. parahaemolyticus, V. harveyi, and V. tubiashii were found to predominance species at all stations. High incidence of erythromycin, ampicillin, and mecillinam resistance was observed among the Vibrio isolates. In contrast, resistance against aztreonam, cefepime, streptomycin, sulfamethoxazole, and sulfonamides was low. All the Vibrio isolates in this study were found to be susceptible to imipenem, norfloxacin, ofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and oxytetracycline. Ninety-five percent of the Vibrio isolates were resistant to one or more different classes of antibiotic, and 20 different resistance antibiograms were identified. Thirty-two distinct plasmid profiles with molecular weight ranging from 2.2 to 24.8 kb were detected among the resistance isolates. This study showed that multidrug-resistant Vibrio spp. were common in the aquatic environments of west coast of Peninsular Malaysia.

Changing characteristics of rotavirus diarrhea in children younger than five years in urban Bangladesh

Background

Childhood rotavirus diarrhea is still one of the major public health challenges. The present study aimed to determine changing characteristics of rotavirus diarrhea in under-5 children at two periods of time.

Methods

We enrolled 5,357 under-5 children with rotavirus positive in two different time periods; i) 1993-1997 (n = 2,493), and ii) 2008–2012 (n = 2,864) considering beginning and ending of two decades. These children were enrolled in the urban Dhaka Hospital of icddr,b.

Results

Overall, proportion of rotavirus was about 25% in 1993–97, which was 42% in 2008–12 (68% rise; p<0.001). Significant higher proportion of children were stunted [38% vs. 22%; aOR-1.33 (95% CI-1.09-1.62)], had vomiting [87% vs. 74%; aOR-2.58 (95% CI-2.02-3.28)], fever [10% vs. 8%; aOR-1.31 (95% CI-0.96-1.78)], family members >5 [38% vs. 35%; aOR-1.32 (95% CI-1.10-1.58)] required more intravenous fluid [9% vs. 3%; aOR-4.93 (95% CI-3.19-7.63)], had higher co-infection with Shigella [3% vs. 1%; aOR-3.36 (95% CI-1.61-7.03)], Vibrio cholerae [4% vs. 1%; aOR-3.70 (95% CI-2.12-6.46)]; and ETEC [13% vs. 7%; aOR-2.21 (95% CI-1.65-2.97)]; however, significantly lower proportion of them used sanitary toilets [54% vs. 78%; aOR-0.66 (95% CI-0.54-0.80)], boiled drinking water [16% vs. 38%; aOR-0.60 (95% CI-0.48-0.74)], used antimicrobial at home [63% vs. 82%; aOR-0.56 (95% CI-0.46-0.69)] and had some or severe dehydration [18% vs. 34%; aOR-0.15 (95% CI-0.12-0.20)] in 1^st observation period compared to that of 2^nd.

Conclusion

Proportion of episodes of under-5 rotavirus diarrhea increased over the period. Concomitant changes in host, socio-demographic and clinical characteristics, and co-infections were also observed. Thus, vaccination campaign which is prevailing in private sector should also be introduced in public sector.