Rotavirus A infection in children under five years old with a double health problem: undernutrition and diarrhoea - a cross-sectional study in four provinces of Mozambique.

BACKGROUND: Mozambique has a high burden of group A rotavirus (RVA) infection and chronic undernutrition. This study aimed to determine the frequency and potential risk factors for RVA infection in undernourished children under 5 years old with diarrhoea in Mozambique. METHODS: The analysis was conducted using data from March 2015 to December 2017, regarding children under 5 years old with at least one type of undernutrition. Anthropometric measures were used to calculate indices of weight-for-age, weight-for-height and height-for-age through the Z-Scores. RVA results were extracted from the National Diarrhoea Surveillance database. Descriptive statistics, chi-square test was used for qualitative variables and organized in contingency tables and 95% Confidence Intervals (CI) were considered for the calculation of RVA infection proportion and in the multiple logistic regression models to estimate the adjusted odds ratios (AOR). RESULTS: Of the 842 undernourished children included in the analysis, 27.2% (95% CI: 24.3-30.3%) were positive for RVA. The rate of RVA infection was 42.7% (95% CI: 38.0-47.5%) in the pre-vaccine period, with great reduction to 12.2% (95% CI: 9.4-15.6%) in the post-vaccine period. Most of the RVA undernourished children had severe wasting (33.3%) and severe stunting (32.0%). The risk of infection was significantly high in children from 0 to 11 months (p-value < 0.001) when compared to the age group of 24-59 months. A higher proportion of RVA infection was detected in households with five or more members (p-value = 0.029). Similar proportions of RVA were observed in children fed only by breast milk (34.9%) and breast milk with formula (35.6%). A higher proportion of undernourished HIV-positive children co-infected with RVA (7.4%) was observed. CONCLUSIONS: The frequency of RVA infection in undernourished children declined following the introduction of the vaccine in Mozambique. Beyond the temporal variation, Maputo province, age and crowded households were also associated to RVA infection. A high proportion of RVA infection was observed in children with severe wasting and a triple burden of disease: undernutrition, RVA and HIV, highlighting the need to conduct follow-up studies to understand the long-term impact of these conditions on children's development.

Intestinal protozoa in hospitalized under-five children with diarrhoea in Nampula - a cross-sectional analysis in a low-income setting in northern Mozambique.

BACKGROUND: In Mozambique, infection by intestinal parasites is reported all over the country. However, infection in children with diarrhoea is mostly focused in the southern region of Mozambique. This work aims to determine the frequency and potential risk factors for infection by Cryptosporidium spp., Giardia lamblia, and Entamoeba histolytica in children under-five years hospitalized with diarrhoea in Hospital Central de Nampula, northern Mozambique. METHODS: A cross-sectional hospital-based surveillance was conducted between March 2015 and January 2018 in children admitted with diarrhoea in Hospital Central de Nampula. Sociodemographic information was obtained through semi-structured interviews applied to the children's caregivers. A single stool sample was collected from each child to detect antigens from Cryptosporidium spp., G. lamblia, and E. histolytica using an immune-enzymatic technique. Crude and adjusted odds ratios (with 95% Confidence Intervals) were obtained by logistic regression models to identify factors associated with infection by Cryptosporidium spp. and G. lamblia. RESULTS: The median age and interquartile intervals of our sample population was 12 months (8-20). Intestinal protozoa were detected in 21.4% (59/276). Cryptosporidium spp. was the most common protozoa (13.9% - 38/274), followed by G. lamblia (9.1% - 25/274) and E. histolytica (0.4% - 1/275). Children with illiterate caregiver's (p-value = 0.042) and undernourished (p-value = 0.011) were more likely to be infected by Cryptosporidium spp. G. lamblia was more common in children living in households with more than four members (p-value = 0.039). E. histolytica was detected in an eleven month's child, co-infected with Cryptosporidium spp. and undernourished. CONCLUSION: Cryptosporidium spp. and Giardia lamblia were the most common pathogenic intestinal protozoa detected in children with diarrhoea hospitalized in the Hospital Central de Nampula. Our findings obtained highlight the importance of exploring the caregiver's education level, children's nutritional status for infections with Cryptosporidium spp., and living conditions, namely crowded households for infections with G. lamblia in children younger than five years.

First molecular identification of mosquito vectors of Dirofilaria immitis in continental Portugal.

BACKGROUND: Canine dirofilariasis due to Dirofilaria immitis is known to be endemic in continental Portugal. However, information about the transmitting mosquito species is still scarce, with only Culex theileri identified to date, albeit with L1-2, through dissection. This study was carried out to investigate the potential vectors of Dirofilaria spp. in continental Portugal. METHODS: Mosquitoes were collected in three distinct seasons (Summer, Autumn and Spring), 2011-2013, in three districts. CDC traps and indoor resting collections were carried out in the vicinity of kennels. Mosquitoes were kept under controlled conditions for 7 days to allow the development of larval stages of Dirofilaria spp.. DNA extraction was performed separately for both head+thorax and abdomen in order to differentiate infective and infected specimens, respectively, in pools, grouped according to the species and collection site (1-40 specimen parts/pool), and examined by PCR using pan-filarial specific primers. Mosquito densities were compared using non-parametric tests. Dirofilaria development units (DDU) were estimated. RESULTS: In total, 9156 female mosquitoes, from 11 different species, were captured. Mosquito densities varied among the 3 districts, according to capture method, and were generally higher in the second year of collections. From 5866 specimens screened by PCR, 23 head+thorax and 41 abdomens pools, corresponding to 54 mosquitoes were found positive for D. immitis DNA. These belonged to 5 species: Culex (Cux) theileri (estimated rate of infection (ERI)=0.71%), Cx. (Cux) pipiens f. pipiens and f. molestus (ERI=0.5%), Anopheles (Ano) maculipennis s.l. (ERI=3.12%), including An. (Ano) atroparvus, Aedes (Och) caspius (ERI=3.73%) and Ae. (Och) detritus s.l. (ERI=4.39%). All but Cx. pipiens, had at least one infective specimen. No D. repens infected specimens were found. Infection rates were: 3.21% in Coimbra, 1.22% in Setúbal and 0.54% in Santarém. DDU were at least 117/year in the study period. CONCLUSIONS: Culex theileri, Cx. pipiens, An. maculipennis s.l. An. atroparvus, Ae.caspius and Ae. detritus s.l. were identified as potential vectors of D. immitis in three districts of Portugal, from Spring to Autumn, in 5 of the 6 collection dates in 2011-2013. Implications for transmission, in the context of climate changes, and need for prophylactic measures, are discussed.