Environmental Sanitation Measures Research Articles

Seroprevalence of Equine Leptospirosis in the State of Goiás, Brazil.

Leptospirosis, caused by Leptospira, is a zoonotic disease that, in horses, is linked to abortions, uveitis, and sporadic occurrences of liver and kidney disease, often resulting in significant economic losses for farmers. Research on the prevalence of leptospirosis in horses in the central-west region of Brazil has been relatively scarce. Thus, the present study aimed to determine the prevalence of leptospirosis in equine herds in the state of Goiás (Central Brazil). Blood samples were collected from 894 equids at 294 randomly selected farms divided into three different strata according to their herd characteristics. The microscopic agglutination test for the detection of anti-Leptospira agglutinins was carried out and the results showed that among the 294 sampled farms, 213 (72.9%; CI 95% 71.7-78.9) had one or more animals positive for leptospirosis, and of the 894 horses sampled, 513 (61.6%; CI 95% 54.3-69.0) were seropositive for leptospirosis. Djasiman, Icterohaemorrhagiae, and Australis were the most prevalent serogroups. The results showed a high prevalence of seropositive animals and a widespread distribution of positive farms in the state of Goiás. Thus, environmental sanitation measures and health education to prevent and control equine leptospirosis in the state are required.

EDITORIAL. Las enfermedades tropicales desatendidas en Venezuela en la era de COVID-19.

Neglected tropical diseases (NTDs) remain a public health problem among vulnerable, marginalized populations. The crisis in Venezuela has caused poverty, malnutrition, the collapse of the health system and public services that have determined the emergence and re-emergence of infectious diseases that exacerbate the problem of NTDs. Due to its economic impact, the COVID-19 pandemic could lead to greater poverty and aggravate the situation. The WHO aims to eliminate 20 NTDs, including geohelminthiasis, as a public health problem by 2030, which is an ambitious plan for Venezuela. To eliminate NTDs as a public health problem, it is necessary to maximize the efforts of the different health disciplines and the application by governments of environmental sanitation measures and the improvement of the standard of living of the affected populations. However, these measures are complex and take time to implement.

Characteristics of Lassa Fever Outbreak in Ondo State, Nigeria, Year 2019

Background: Lassa fever (LF) is an acute viral haemorrhagic illness of a 2–21-day incubation period that occurs in West Africa. It is endemic in Nigeria and peaks during the first 12 weeks of the year. On January 22, 2019, the Nigeria Centre for Disease Control (NCDC) declared an outbreak of LF following an upsurge of LF cases in the country. A total of 213 confirmed cases including 41 deaths were reported from sixteen states including Ondo State. A multi-sectoral national rapid-response-team (RRT) was deployed to Ondo State to characterise the outbreak, assess its determinants, and institute control measures. Methods: An Emergency Operations Center (EOC) was activated to coordinate activities. We defined a suspected case as anyone with one or more of the following symptoms: malaise, fever, headache, sore throat, cough, vomiting and either history of contact with rodents, or a probable or confirmed LF case in the past 21 days, or any person with inexplicable bleeding between January 1, 2019, to February 26, 2019, in Ondo State. A confirmed case was any suspected case with laboratory confirmation. We conducted active case search, collected data using the LF case investigation form and reviewed the existing line list. We conducted contact tracing in hospitals and affected Local Government Areas (LGA). Data was analysed using and Epi info 7.0. Results: We identified 287 LF suspected cases in 6 LGAs; 118 were confirmed with 21 deaths (case fatality rate: 17.8%). The mean age was 39.2 ±20 years with a male-to-female ratio of 1.3:1. Of the 1,269 contacts line-listed, 20 became symptomatic, while 14 (70.0%) were confirmed positive. The secondary attack rate was 1.1%. Conclusion: The confirmed cases were more of primary cases, hence the need to focus more on reducing rodent-to-human transmission of LF. We recommend continuous education on community and health facility infection prevention control, contact tracing and enforcement of environmental sanitation measures across the state to mitigate future outbreaks

Trends in pattern of communicable diseases during COVID-19 lockdown in Kerala.

Dear Editor, Kerala is witnessing an increase in instances of vector-borne diseases and water-borne infections in recent times. [1] The state witnessed Nipah virus outbreak during 2018 and 2019. [2] COVID-19 pandemic surfaced in Kerala on 30 January 2020 and the cases increased during the month of March. [3] We performed a retrospective analysis of communicable disease reported in Kerala with the data retrieved from the website archive of Integrated Disease Surveillance Programme and tuberculosis notification website. [45] The incidence of various communicable diseases were compared during the study period (month of March, April and May 2020 where cases of COVID-19 were reported and containment strategies were implemented) with similar months for last four years (2016 to 2019) as per availability of the data. There was a decrease in the incidence of chickenpox cases by 22.3%, 21.5% and 66.3%, respectively, during the month of March, April and May 2020 in comparison with similar months of 2019. Tuberculosis cases decreased by 19.4%, 35.77% and 19.41% during the study period in comparison with similar months in 2019 [Table 1]. The incidence of H1N1, hepatitis A and typhoid cases decreased during the study period in comparison with similar months of 2019. There was a trend of increase in incidence of ADD cases during the month of May, but during 2020 the percentage increase was lowest among the last 4 years. Malaria and Chikungunya cases reported low but the incidence of dengue cases was slightly more in study period in comparison with similar period in 2019 [Table 1].Table 1: Incidence of communicable diseases in Kerala during the month of March, April and May 2016-2020.The containment strategies against COVID-19 in Kerala prevent the interaction between the agent and host in a favourable environment which helps to contain communicable diseases [Figure 1]. Overcrowding which was prevented by lockdown measures, life style and behavioural changes like social distancing, respiratory hygiene/cough etiquette helped to decrease other respiratory infections like tuberculosis, chickenpox and H1N1 along with COVID-19.Figure 1: Epidemiological triad showing the factors prevented the interaction between agent, host and environmentLockdown measures confined individuals at home which removed the possibility of food and water intake from contaminated environment and routine hand washing practices curtailed the intestinal diseases like hepatitis A, typhoid and acute diarrheal diseases. It was also noticed a decrease in malaria and chikungunya cases which may be due to the environmental sanitation measures underwent during the pandemic [Table 1]. The response of health system to the pandemic, its containment strategies which was implemented through community participation and intersectorial coordination along with lifestyle and behavioral modification of people helped in control of other communicable diseases in the state. There may be some other reasons also for the decrease in the incidence of communicable diseases as people might have ignored slight manifestations of the disease because of the fear to go to hospitals. Health system is overwhelmed with COVID-19 cases which may result in less testing and under reporting of other communicable diseases. Control of infectious diseases is a difficult challenge for our public health systems; however, we believe that covid-19 response and strengthened containment strategies had an impact on the incidence of communicable diseases which need to be carried over. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. Acknowledgement The authors thank Dr. Binod Kumar Patro, Additional Professor, AIIMS, Bhubaneswar for his guidance and review of the article.

Seroepidemiology of leptospirosis and toxoplasmosis in equines in the northwest region of Paraná

Leptospirosis and toxoplasmosis are diseases that may affect man and domestic and wild animals. They also have wide geographical distributions and thus cause large public health issues. The objective of the current study was to conduct leptospirosis and toxoplasmosis seroepidemiology in horses used for animal traction in small rural propertiesof the municipality of Umuarama, in northwest region of the state of Paraná, Brazil. Blood samples were collected from 312 horses from 87 small farms. Microscopic agglutination tests (MAT) and indirect immunofluorescence (IIF) analysis were performed on sera to detect leptospirosis and toxoplasmosis, respectively. These were performed in conjunction with an epidemiological questionnaire. The MAT results included 180 (57.69%) samples that were considered reactive with titers between 100 and 12800 for one or more serovars. Thirty-three (10.57%) samples subjected to IIF were considered reactive, with titers ranging between 64 and 1024. From the analyzed variables, contact with wild animals (p= 0.012) and animal exchange between properties (p = 0.004) were associated with toxoplasma infection. The study revealed that horses in the northwestern region of Paraná were exposed to Leptospira spp. and Toxoplasma gondii, with an insignificant implication of the animals’ clinical condition; however, since it is possible for animals to transmit infection to other animals as well as humans via the intermittent shedding of leptospires through urine into the environment, it may be considered a problem of one health. As for the presence of T. gondii antibodies, these horses played the role of sentinel of the infection. Environmental sanitation measures, serological studies of herds, control of rodents and felids on properties, and the dissemination of information about these diseases are relevant for disease control at the study site.

Impact on prevalence of intestinal helminth infection in school children administered with seven annual rounds of diethyl carbamazine (DEC) with albendazole

One third of the world's population is infected with one or more of the most common soil-transmitted helminths (STH). Albendazole (ALB) is being administered with diethyl carbamazine (DEC) in filariasis endemic areas to eliminate lymphatic filariasis (LF) and helminth infections. In this study, the cumulative impact of seven annual rounds of mass drug administrations (MDA) of DEC and ALB on STH infection in school children in selected villages in southern India was determined. During 2001-2010, seven MDAs were implemented by the Tamil Nadu s0 tate h0 ealth d0 epartment, India. LF and STH infections were monitored in school children from 18 villages of the two treatment arms (viz, DEC alone and DEC+ALB). Kato-Katz cellophane quantitative thick smear technique was employed to estimate STH infections at three weeks, six months and one year post MDA. Prior to treatment, an overall STH prevalence was 60 per cent. After each MDA, infection markedly reduced at three weeks post-treatment in both the arms. The prevalence increased at six months period, which was maintained up to one year. After seven rounds of MDA, the infection reduced from 60.44 to 12.48 per cent in DEC+ALB arm; while the reduction was negligible in DEC alone arm (58.77 to 52.70%). Seven rounds of MDA with DEC+ALB reduced the infection load significantly, and further sustained low level of infection for 10 years. However, complete parasite elimination could not be achieved. To curtail STH infection in the community, MDA should be regularized and environmental sanitation measures need to be improved by effective community-based campaigns.

Hydrochemical trends for public supply well fields in The Netherlands (1898–2008), natural backgrounds and upscaling to groundwater bodies

Summary Statistical trend analysis is applied to a 110 years long groundwater quality time series from the national network of public supply well fields (PSWFs) in The Netherlands. Such a groundwater quality monitoring network should be available in many countries, so that approaches and experiences presented here could be of interest world wide. Trendless concentration data series measured in the early years, which should bear the least anthropogenic influences, are selected to quantify the regional natural background concentration levels (NBLs) of groundwater resources at the depth of abstraction. Trends in the period 1960–2005, which contained a more homogeneous data set, are normalized to drinking water standards, mapped in planar view and cross sections, and used to identify the responsible hydrochemical processes. Seven representative trend bundles are defined by aggregation of trends for individual chemical parameters. Trend reversals due to either environmental sanitation measures or well field adaptation measures are identified by comparing significant trends obtained for two different periods within the time series. Natural background levels (NBLs) for individual PSWFs are upscaled to the national groundwater body level (as reported to EU), by aggregating them according to a PSWF typology based on a Hydrochemical System Analysis. This aggregation method groups together PSWFs that deliver waters of the same origin and similar hydrogeochemical environment. PSWFs delivering old groundwaters with a very stable quality are clearly differentiated from PSWFs pumping highly vulnerable aquifers characterized by strongly deteriorating water quality trends. Results are presented on national maps of The Netherlands with NBLs and water quality trends for selected major constituents. A normalized concentration change index (NCC) is defined and mapped to relate the quality difference between a recent survey (in 2008) and calculated NBLs, to the EU drinking water standards.

A serological study of Cryptosporidium transmission in a periurban area of a Brazilian Northeastern city

To study the prevalence of Cryptosporidium infection by measuring the levels of anti-Cryptosporidium IgG antibodies among people inhabiting three neighbourhoods of a periurban area of Salvador, Northeast of Brazil; and to investigate the effects of environmental sanitation measures, hygienic habits and household water supply, storage and handling on the frequency of these antibodies in sera of the studied population. Cryptosporidium inter-household transmission was studied by comparing the frequency of anti-Cryptosporidium IgG antibodies among people inhabiting areas with or without different environmental sanitation measures and intra-household transmission by comparing the presence of these antibodies in families with or without cases of diarrhoea, associated with the presence of Cryptosporidium oocysts in their stools. Children or family members with diarrhoeal episodes were evaluated parasitologically for Cryptosporidium infection by testing stool specimens with the Ritchie-modified formol-ether concentration and the acid-fast staining methods. All groups were serologically evaluated for parasite exposure by an indirect enzyme-linked immunosorbent assay. A statistically significant difference was detected in the prevalence of Cryptosporidium infection between area 1 which had no environmental sanitation measures and area 3 which had improved environmental sanitation measures (P = 0.044). Most of the hygienic habits investigated did not correlate with the presence of anti-Cryptosporidium antibody in sera of the population studied. However, positive associations were found between both poor household water supply (OD = 0.17; 90% CI = 0.09-0.32; P = 0.0001) and drinking unboiled/unfiltered water (OD = 0.40; 90% CI = 0.24-0.67; P = 0.0002) with high levels of anti-Cryptosporidium antibodies in sera. These data suggest that although uncorrected household water supply, storage and handling play an important role on Cryptosporidium transmission in periurban areas of developing country cities, like Salvador, Brazil, inadequate environmental conditions may also contribute to the spread of this parasite.

Seroprevalence of toxocariasis in schoolchildren in Trinidad

The seroprevalence of toxocariasis was investigated in 1997/98 in 1009 schoolchildren (aged 5–12 years) throughout Trinidad. Infection, as measured by titre, was found to be high compared to values obtained from children in other countries. Using an excretory-secretory antigen and performing an ELISA test, it was found that 62·3% of children had an IgG antibody titre of ≥ 1: 100, indicating exposure to the parasite, while 27·2% had a titre of ≥ 1: 800, indicating a current or recent infection. Relationships were explored between seroprevalence and host factors including age, sex, school location, and other risk factors including geophagia, thumb-sucking, presence of other gastrointestinal-tract parasitism and pet ownership. There was no significant relationship between age and the presence of current or recent infection ( P = 0·746). Boys were significantly more commonly infected than girls as were the attendees of rural schools versus urban schools ( P < 0·001). The percentage of seropositivity among children varied widely from school to school. Pet ownership and the absence of pipe-borne water in the household were found to be significantly associated with positive serology ( P < 0·05). Clinical symptoms mostly associated with positive serology were eczema, seizures and chronic cough. Recommendations derived from this study include health education in order to increase the public awareness on the transmission of the disease, de-worming all dogs and cats periodically and the curbing of stray dogs and cats. Environmental sanitation measures should include keeping children away from contaminated areas and practising proper hygiene after play.

Juvenile subcutaneous abscessation of sheep caused by Streptococcus faecium.

Summary : A clinical syndrome in sheep, which persisted since several years at the Hawatka Breeding Station (Assiut province) and was cha­ racterised by subcutaneous abscesses mostly affecting young animals (between 4 months and two years of age), is described. No deaths were observed but the condition appeared to be incurable. It had never been reported elsewhere in Egypt. The causative pathogen was isolated and identified as Streptococcus faecium. To control the disease, the following actions were undertaken and gave very satisfactory results : surgical intervention on diseased animals; hygienic and environmental sanitation measures, disinfection; protection of susceptible animals through vaccination using either a kil­ led formolised vaccine, made from locally isolated strains of S. faecium and containing Freund's incomplete adjuvant, or BCG, acting as a non-specific immunopotentiator. Epidemiological and immunological aspects of these findings are discussed.

Control of an outbreak of rove beetle dermatitis in an isolated camp in a game reserve

An incapacitating outbreak of rove beetle dermatitis (Paederus sabaeus Er.: Staphylinidae) which occurred in an isolated game reserve camp was correctly diagnosed after comparing facilities in the camp with those in a nearby disease-free camp. The problem was quickly controlled by reducing the number of artificial lights, by changing the mercury tube lights to ordinary light bulbs and by conducting environmental sanitation measures, including fumigation of the compound with HCH (BHC, lindane). At the time of implementing the control measures, work on feasibility studies for a large dam project had come to a standstill.