Sensitivity of the acute flaccid paralysis surveillance system for poliovirus in South Africa, 2016-2019

Introduction

Global poliovirus eradication is a public health emergency of international concern. The acute flaccid paralysis (AFP) surveillance programme in South Africa has been instrumental in eliminating polioviruses and keeping the country poliovirus free.

Gap statement

The sensitivity of surveillance for polioviruses by every African country is of global interest in the effort to ensure global health security from poliovirus re-emergence.

Aim

To describe the epidemiology of polioviruses from AFP cases and environmental samples in South Africa and to report the performance of the AFP surveillance system for the years 2016–2019 against targets established by the World Health Organization (WHO).

Methods

Stool specimens from AFP or suspected AFP cases were received and tested as per WHO guidelines. Environmental samples were gathered from sites across the Gauteng province using the grab collection method. Concentration was effected by the two-phase polyethylene glycol method approved by the WHO. Suspected polioviruses were isolated in RD and/or L20B cell cultures through identification of typical cytopathic effects. The presence of polioviruses was confirmed by intratypic differentiation PCR. All polioviruses were sequenced using the Sanger method, and their VP1 gene analysed for mutations.

Results

Data from 4597 samples (2385 cases) were analysed from the years 2016–2019. Two cases of immunodeficiency-associated vaccine-derived poliovirus (iVDPV) type 3 were detected in 2017 and 2018. A further 24 Sabin type 1 or type 3 polioviruses were detected for the 4 years. The national surveillance programme detected an average of 3.1 cases of AFP/100 000 individuals under 15 years old (2.8/100 000–3.5/100 000). The stool adequacy of the samples received was 53.0 % (47.0–55.0%), well below the WHO target of 80 % adequacy. More than 90 % of results were released from the laboratory within the turnaround time (96.6 %) and non-polio enteroviruses were detected in 11.6 % of all samples. Environmental surveillance detected non-polio enterovirus in 87.5 % of sewage samples and Sabin polioviruses in 12.5 % of samples.

Conclusion

The AFP surveillance programme in South Africa is sensitive to detect polioviruses in South Africa and provided no evidence of wild poliovirus or VDPV circulation in the country.

Rapid Screening for Non-falciparum Malaria in Elimination Settings Using Multiplex Antigen and Antibody Detection: Post Hoc Identification of Plasmodium malariae in an Infant in Haiti

Haiti is targeting malaria elimination by 2025. The Grand'Anse department in southwestern Haiti experiences one-third to half of all nationally reported Plasmodium falciparum cases. Although there are historical reports of Plasmodium vivax and Plasmodium malariae, today, non-falciparum infections would remain undetected because of extensive use of falciparum-specific histidine-rich protein 2 (HRP2) rapid diagnostic tests (RDT) at health facilities. A recent case-control study was conducted in Grand'Anse to identify risk factors for P. falciparum infection using HRP2-based RDTs (n = 1,107). Post hoc multiplex Plasmodium antigenemia and antibody (IgG) detection by multiplex bead assay revealed one blood sample positive for pan-Plasmodium aldolase, negative for P. falciparum HRP2, and positive for IgG antibodies to P. malariae. Based on this finding, we selected 52 samples with possible P. malariae infection using IgG and antigenemia data and confirmed infection status by species-specific PCR. We confirmed one P. malariae infection in a 6-month-old infant without travel history. Congenital P. malariae could not be excluded. However, our finding-in combination with historical reports of P. malariae-warrants further investigation into the presence and possible extent of non-falciparum malaria in Haiti. Furthermore, we showed the use of multiplex Plasmodium antigen and IgG detection in selecting samples of interest for subsequent PCR analysis, thereby reducing costs as opposed to testing all available samples by PCR. This is of specific use in low-transmission or eliminating settings where infections are rare.

Towards the elimination of Plasmodium vivax malaria: Implementing the radical cure

In this review for the Vivax malaria collection, Kamala Thriemer and colleagues explore efforts to eliminate P. vivax malaria.

Exploring factors affecting quality implementation of lymphatic filariasis mass drug administration in Bole and Central Gonja Districts in Northern Ghana

Ghana has been implementing Mass Drug Administration (MDA) since the year 2001, and Lymphatic Filariasis transmission has been interrupted in 76 out of the 98 targeted districts. The remaining districts have a microfilaria prevalence above the 1% threshold needed for the interruption of transmission. This study assesses the level of lymphatic filariasis MDA coverage and explored factors affecting the quality of implementation of the MDA in the Bole and Central Gonja Districts of Northern Ghana. A concurrent mixed methods study design approach was used to provide both a quantitative and qualitative insight. A descriptive analysis was carried out, and the results are presented in tables and charts. The transcripts of the qualitative interviews were imported into Nvivo and framework methods of analysis were used. The results were summarized based on the themes and buttressed with narratives with key quotes presented within the texts. The overall MDA coverage in Central Gonja is 89.3% while that of Bole district is 82.9%. Refusal to ingest the drug and adverse drug reactions were higher in Bole district than the Central Gonja District. The persistent transmission of lymphatic filariasis in Bole District was characterized by poor community mobilization and sensitization, nonadherence to the directly observed treatment strategy, refusal to ingest the drug due to the fear of adverse drug reactions, inadequate knowledge and misconceptions about the disease. Reported mass drug administration coverage will not necessarily result into interruption of transmission of the disease without strict compliance to the directly observed treatment strategy, strong stakeholder engagement coupled with evidence-based context-specific multi-channel community education strategies with key educational messages on the cause of the disease and adverse drug reactions. While the clock for the elimination of lymphatic filariasis by the year 2020 and meeting of the Sustainable Development Goal 3 target 3.3 by 2030 is ticking, there is an urgent need for a concerted effort to improve the fidelity of the ongoing lymphatic filariasis MDA campaigns in the Bole District of Northern Ghana.

After 18 years of implementing the global strategy to eliminate lymphatic filariasis in Ghana, the prevalence of the transmission of the disease is still above the threshold needed to interrupt transmission of the disease as a public health problem in some districts. This study showed that, the persistent transmission of the lymphatic filariasis in the Bole District is characterized with a refusal to ingest the drug; reported adverse drug reactions; poor knowledge and misconceptions of the disease, and poor adherence to the mass drug administration protocol. High reported mass drug administration coverage will not lead to interruption of transmission of lymphatic filariasis without strict adherence to the direct observe treatment strategy, strong stakeholder engagement coupled with evidence-based context-specific multi-channel community education strategies with key educational messages on adverse drug reactions and the cause of the disease.

The impact of a prolonged ebola outbreak on measles elimination activities in Guinea, Liberia and Sierra Leone, 2014-2015

INTRODUCTION

Guinea, Sierra Leone and Liberia have attained significant reduction in measles incidence between 2004 and 2013. The Ebola outbreak in 2014-2015 in West Africa caused significant disruption of the health service delivery in the three worst affected countries. The magnitude of the impact on the immunization program has not been well documented.

METHODS

We reviewed national routine immunization administrative coverage data as well as measles surveillance performance and measles epidemiology in the years before, during and after the EVD outbreak in Guinea, Liberia, Sierra Leone.

RESULTS

Both Liberia and Guinea experienced a sharp decline of more than 25% in the monthly number of children vaccinated against measles in 2014 and 2015 as compared to the previous years, while there was no reported decline in Sierra Leone. Guinea and Liberia experienced a decline in measles surveillance activity and performance indicators in 2014 and 2015. During this period, there was an increase in measles incidence and a decline in the mean age of measles cases reported in Liberia and Sierra Leone. Guinea started reporting high measles incidence in 2016. All three countries organized measles supplemental immunization activities by June 2015. Liberia achieved 99% administrative coverage, while Guinea and Sierra Leone attained 90.6% and 97.2% coverage respectively. There were no severe adverse events reported during these mass vaccination activities. The disruptive effect of the Ebola outbreak on immunization services was especially evident in Guinea and Liberia. Our review of the reported administrative vaccination coverage at national level does not show significant decline in measles first dose vaccination coverage in Sierra Leone as compared to other reports. This may be due to inaccuracies in coverage monitoring and data quality problems. The increases in measles transmission and incidence in these three countries can be explained by the rapid accumulation of susceptible children. Despite the organization of mass vaccination activities, measles incidence through 2017 has remained higher than the pre-Ebola period in all three countries.

CONCLUSION

The Ebola outbreak in West Africa significantly affected measles vaccination coverage rates in two of the three worst affected countries, and led to persistent gaps in coverage, along with high measles incidence that was documented until two years after the end of the Ebola outbreak. Liberia and Sierra Leone have demonstrated coverage improvements after the end of the Ebola outbreak.

The African Region early experience with structures for the verification of measles elimination – a review

Substantial progress has been achieved in the last two decades with the implementation of measles control strategies in the African Region. Elimination of measles is defined as the absence of endemic transmission in a defined geographical region or country for at least 12 months, as documented by a well-performing surveillance system. The framework for documenting elimination outlines five lines of evidence that should be utilized in documenting and assessing progress towards measles elimination. In March 2017, the WHO regional office for Africa developed and disseminated regional guidelines for the verification of measles elimination. As of May 2019, fourteen countries in the African Region have established national verification committees and 8 of these have begun to document progress toward measles elimination. Inadequate awareness, concerns about multiple technical committees for immunization work, inadequate funding and human resources, as well as gaps in data quality and in the implementation of measles elimination strategies have been challenges that hindered the establishment and documentation of progress by national verification committees. We recommend continuous capacity building and advocacy, technical assistance and networking to improve the work around the documentation of country progress towards measles elimination in the African Region.

[Analysis of evaluation results of malaria elimination in Jiujiang City]

OBJECTIVE

To analyze the evaluation results of malaria elimination and summarize the experience in Jiujiang City, so as to provide the evidence for formulating the surveillance work plan post-malaria elimination.

METHODS

According to the requirements and arrangements of Jiangxi Eliminating Malaria Action Plan (2010 - 2020), the evaluation of malaria elimination was completed in all 13 counties (cites and districts) of Jiujiang City from 2013 to 2016, and the data were collected and analyzed.

RESULTS

In Jiujiang City, the last local malaria case was reported in 2008. From 2010 to 2016, there were 20 imported malaria cases reported, including 12 cases of falciparum malaria, 7 cases of vivax malaria, and 1 case of mixed infection. Totally 67 501 fever patients were tested for Plasmodium and 13 cases were positive, with the positive rate of 0.02%. The comprehensive evaluation scores were between 88.75 and 98.15 in all the 13 counties (cities and districts), which meant they all reached the evaluative criteria.

CONCLUSIONS

All 13 counties (cities and districts) of Jiujiang City have passed the city level evaluative criteria of malaria elimination, and the key work should be the prevention and surveillance of imported malaria in the future.

Improved assessment of mass drug administration and health district management performance to eliminate lymphatic filariasis

Lymphatic filariasis (LF) elimination as a public health problem requires the interruption of transmission by administration of preventive mass drug administration (MDA) to the eligible population living in endemic districts. Suboptimal MDA coverage leads to persistent parasite transmission with consequential infection, disease and disability, and the need for continuing MDA rounds, requiring considerable investment. Routine coverage reports must be verified in each MDA implementation unit (IU) due to incorrect denominators and numerators used to calculate coverage estimates with administrative data. IU are usually the health districts. Coverage is verified so IU teams can evaluate their outreach and take appropriate action to improve performance. Mozambique and the Democratic Republic of Congo (DRC) have conducted MDA campaigns for LF since 2009 and 2014, respectively. To verify district reports and assess the declared achievement using administrative data of the minimum 80% coverage of eligible people (or 65% of the total population), both countries conducted rapid probability surveys using Lot Quality Assurance Sampling (LQAS)(n = 1102) in 2015 and 2016 in 58 IU in 49 districts. The surveys identified IU with suboptimal coverage, reasons residents did not take the medication, place where the medication was received, information sources, and knowledge about diseases prevented by the MDA. LQAS identified four inadequately covered IU triggering district team performance reviews with provincial and national teams and district retreatment. Provincial estimates using probability samples (weighted by populations sizes) were 10 and 17 percentage points lower than reported coverage in DRC and Mozambique. The surveys identified: absence from home during annual MDA rounds as the main reason for low performance and provided valuable information about pre-campaign and campaign activities resulting in improved strategies and continued progress towards elimination of LF and co-endemic Neglected Tropical Diseases.

Global elimination of lymphatic filariasis (LF) is achieved through treatment of at-risk populations with annual or bi-annual mass drug administration campaigns. In Africa campaigns need to be completed in 32 countries with 343 million people at risk. The World Health Organisation recommends verification of the campaign’s administrative records using household cluster surveys at least once every 5-years. However, cluster surveys are expensive and usually completed in a few districts only or at sub-national levels. Together with National Programmes in Mozambique and the Democratic Republic of the Congo (DRC) we adapted Lot Quality Assurance Sampling (LQAS) methods to verify campaign coverage because it is relatively inexpensive in comparison to other survey approaches, provides information and facilitates actions at the Implementation Unit (IU) level, which is usually the district. LQAS signals IU whose performance is likely to need improvement because MDA coverage is below the coverage target. Our results show consistently that administrative records over-estimated campaign coverage and did not detect implementation and coverage problems due to errors in numerators and denominators, incorrect reporting, and/or incorrect aggregation of tally sheets. The LQAS verification approach prompted immediate action to remedy coverage shortfalls averting persistent LF transmission and disease, and the costs associated with failed campaigns. Our study demonstrates that a rapid probability sample to verify coverage provides district teams with information after each campaign which can be used for action, and that one coverage survey every 5-years is insufficient for infectious disease elimination in highly endemic settings where achievement of optimal coverage is essential. It also demonstrates that LQAS provides a decentralised assessment, sensitive for detecting and ameliorating programme bottlenecks and can be used to verify MDA in other countries.

Antituberculous fight in the Maghreb: the balance sheet

The fight against tuberculosis remains a priority for world leaders: a re-emerging disease in developed countries, endemic elsewhere, it was declared in 1993, as a "world emergency" by the World Health Organization (WHO). The aim of programs is to prevent infection from spreading and perpetuating; the recommended strategies were the subject of common consent by expert committees convened by international agencies, primarily the WHO. As a result, programs of the Maghreb countries have great similarities. Though the regression in cases's number, especially primary and post-primary forms, as well as extensive, deleterious pulmonary tuberculosis in adults, the endemic persists. The proportion of extra-pulmonary tuberculosis (PET) is high. Control of "contacts" would be lacking or delayed in almost half of the cases. The cover by an effective treatment of these cases in Libya and in Mauritania stays below the required 85 %. Taken as a whole, the constituent countries of the Maghreb entity count approximately 78 000 tuberculosis patients for a population close to 100 million inhabitants, with an incidence rate of 76 for 100 000. Reducing the incidence of tuberculosis by 90 % and the mortality by 95%, to ensure that by the end of 2035 tuberculosis is no longer a public health problem is a goal within the reach of Maghreb countries. It can be postulated that by this deadline, the conditions for success will be met.

Epidemiology of malaria and elimination prospects in Maghreb Countries

BACKGROUND

Faced with the challenges of immigration, the opening of the Trans-Saharan road and the increase in the volume of trade with sub-Saharan Africa, there is a steady increase in the number of malaria cases. An introduction of the disease in the Maghreb is possible.

OBJECTIVE

The general objective is to take stock of the epidemiological situation and the malaria control strategy in the Maghreb countries.

METHODS

This is a synthesis of data from a literature search on: PubMed (publications), International and national reports (epidemiology and strategies).

RESULTS

In 1979, Tunisia became the second Maghreb country to eliminate malaria after Libya (the last local case in 1973). In 1997, when 76 cases were recorded, Morocco embarked on a new national strategy aimed at the elimination of indigenous malaria by the end of 2005. In Algeria, after a phase of control by existence of P. vivax and P. malaria microspheres, the country is in the maintenance phase and no cases were recorded between 2013 and 2016. In Mauritania, even though malaria transmission is generally low, this parasitosis remains a problem public health. And the strategies of struggle and the contribution of scientific research remain below expectations.

CONCLUSION

With the exception of Mauritania, the countries of the Great Arab Maghreb have practically eradicated malaria, even though the maintenance phase is underway in Algeria and cases imported from sub-Saharan Africa continue to be registered.

National, Regional and Global Certification Bodies for Polio Eradication: A Framework for Verifying Measles Elimination

The Global Certification Commission (GCC), Regional Certification Commissions (RCCs), and National Certification Committees (NCCs) provide a framework of independent bodies to assist the Global Polio Eradication Initiative (GPEI) in certifying and maintaining polio eradication in a standardized, ongoing, and credible manner. Their members meet regularly to comprehensively review population immunity, surveillance, laboratory, and other data to assess polio status in the country (NCC), World Health Organization (WHO) region (RCC), or globally (GCC). These highly visible bodies provide a framework to be replicated to independently verify measles and rubella elimination in the regions and globally.

Factors Associated with Ivermectin Non-Compliance and Its Potential Role in Sustaining Onchocerca volvulus Transmission in the West Region of Cameroon

Background

Community Directed Treatment with ivermectin is the cornerstone of current efforts to eliminate onchocerciasis. However recent studies suggest there are foci where long-term annual distribution of the drug alone has failed to ensure elimination thresholds are reached. It is important to achieve high levels of compliance in order to obtain elimination targets. An epidemiological and entomological evaluation conducted in the western region of Cameroon in 2011 revealed that two health districts remained with a high prevalence of infection, despite long-term distribution of ivermectin since 1996. This paper explores potential factors that may have contributed to the non-interruption of transmission, focusing on ivermectin treatment compliance and the importance of systematic non-compliance within the population.

Methodology/Principal findings

A mixed methods approach was used, including a population-based survey to assess treatment compliance and factors associated and qualitative assessments including focus group discussions and in-depth interviews with key programme stakeholders and drug distributors. Compliance was reported at 71.2% (95%CI: 61.7–79.2%;n = 853/1198). The key factors related to compliance in the most recent round related to either programmatic and delivery issues, primarily absenteeism at the time of the campaign or alternatively individual determinants. An individual’s experience of side effects in the past was strongly associated with non-compliance to ivermectin. Other factors included ethnicity, how long lived in the village and age. There was a high percentage of reported systematic non-compliance at 7.4% (95% CI: 4.3–12.3%; n = 86/1165), higher amongst females. This group may be important in facilitating the sustainment of on-going transmission.

Conclusions/Significance

Efforts to reduce the number of systematic non-compliers and non-compliance in certain groups may be important in ensuring the interruption of transmission in the study area. However, in areas with high pre-control force of transmission, as in these districts, annual distribution with ivermectin, even if sustaining high levels of compliance, may still be inadequate to achieve elimination. Further studies are required to better understand the transmission dynamics and focus of on-going transmission in the study districts.

Community Directed Treatment with ivermectin is the cornerstone of current efforts to eliminate onchocerciasis. Ivermectin distribution alone has been shown to be able to interrupt transmission but there are foci where long-term distribution of the drug alone has failed to ensure elimination thresholds are reached. Two health districts in the western region of Cameroon remain with high prevalence of infection despite annual distribution of ivermectin since 1996. The study aims to explore factors related to non-compliance in two health districts in the west region of Cameroon. Nearly 30% of the population did not take ivermectin during the most recent round of mass drug administration and there was a significant proportion of the population that had reportedly never taken the drug. The key factors related to drug compliance in the most recent round, related to either programmatic and delivery issues, primarily absenteeism at the time of the campaign, or alternatively individual determinants, such as side effects associated with the drug, ethnicity, age and years lived in the village. Efforts to reduce the number of systematic non-compliers and non-compliance in certain groups are likely to be important in ensuring the interruption of transmission in the study area.

Forced removals embodied as tuberculosis

South Africa has one of the worst tuberculosis burdens in the world. Several ecological forces have contributed to this, including high HIV prevalence; failing TB control strategies; crowded, poorly ventilated indoor environments-including the complex web of political and economic interests which produce them; the development of racial capitalism; and mining and migration. In the following study, we measure CO2 levels in public transport to investigate the role extended commutes from peri-urban settlements to urban sites of work-a direct result of forced removals-potentially play in propagating the TB epidemic in Cape Town, South Africa.

Factors influencing the use of topical repellents: implications for the effectiveness of malaria elimination strategies

In Cambodia, despite an impressive decline in prevalence over the last 10 years, malaria is still a public health problem in some parts of the country. This is partly due to vectors that bite early and outdoors reducing the effectiveness of measures such as Long-Lasting Insecticidal Nets. Repellents have been suggested as an additional control measure in such settings. As part of a cluster-randomized trial on the effectiveness of topical repellents in controlling malaria infections at community level, a mixed-methods study assessed user rates and determinants of use. Repellents were made widely available and Picaridin repellent reduced 97% of mosquito bites. However, despite high acceptability, daily use was observed to be low (8%) and did not correspond to the reported use in surveys (around 70%). The levels of use aimed for by the trial were never reached as the population used it variably across place (forest, farms and villages) and time (seasons), or in alternative applications (spraying on insects, on bed nets, etc.). These findings show the key role of human behavior in the effectiveness of malaria preventive measures, questioning whether malaria in low endemic settings can be reduced substantially by introducing measures without researching and optimizing community involvement strategies.

[Effect of soil-transmitted helminthes control through mass deworming and latrine improvement]

OBJECTIVE

To evaluate the effect of soil-transmitted helminthes control through mass deworming and latrine improvement in rural areas.

METHODS

The data including mass deworming (1998-2000) and latrine improvement (2001-2010) were collected, summarized and analyzed in Danyang City. The infection rate of the soil-transmitted helminthes was monitored annually by using Kato-Katz method from 2001 to 2010. In addition, 2 villages with the improved latrines strategy and one village without the strategy were selected for hygienic evaluation.

RESULTS

Totally 1 130 000 person-times of mass deworming were carried out in Danyang City from 1998 to 2000, and the infection rate of soil transmitted helminthes of human was decreased from 40.82% to 1.10%. The infection rate (2.49%-4.81%) was bounced in the first five years (from 2001 to 2005) after mass deworming, while it gradually declined in the following five years (from 2006 to 2010) and maintained at a low level (0.07%-0.52%), and there was a significant difference between the average infection rates during the above two stages (χ2 = 353.83, P < 0.01). There was a negative correlation between the coverage rate of harmless latrine and the infection rate (r = -0.83, P < 0.01).

CONCLUSION

The mass deworming and latrine improvement are effective measures for the control of soil-trans-mitted helminthes infection in rural areas.

[Analysis of schistosomiasis situation at a surveillance site in Kailhua County, Zhejiang Province from 2008 to 2014]

OBJECTIVE

To master the dynamics of schistosomiasis situation in Kaihua County, so as to provide the evidence for formulating the prevention and control scheme.

METHODS

According to the "Schistosomiasis Monitoring Work Program in Zhejiang Province", the Oncomelania hupensis snail status, schistosome infections of residents and livestock, and the influencing factors were investigated.

RESULTS

Totally 62 snail sites were discovered, the area with snails was 2.30 hm2, the snail density was 0.023 snail/0.1 m2, and the snail status declined with time. No schistosome infected snails, local residents, mobile people or livestock were found.

CONCLUSION

The endemic situation of schistosomiasis is stable in Kaihua County, but the surveillance of snail situation and mobile population is still needed.

[Endemic situation of schistosomiasis in Tongling County of Anhui Province from 2009 to 2014]

OBJECTIVE

To understand the endemic situation of schistosomiasis in Tongling County of Anhui Province, so as to provide the evidence for summarizing the "Twelfth Five-Year Plan" and formulating the "Thirteenth Five-Year Plan".

METHODS

The data of schistosomiasis control reports and other information about Oncomelania hupensis status and schistosomiasis situation of population and livestock were collected and analyzed statistically in Tongling County from 2009 to 2014.

RESULTS

From 2009 to 2014, the schistosome infection rate and blood positive rate of the population decreased significantly, and only one case of acute schistosome infection was found in 2009. The schistosome infection rate of livestock decreased significantly, and the decreasing rate was 91.10% from 2009 to 2010. From 2009 to 2014, the snail area and average density of living snails presented decreasing trends but the densities of living snails increased in 2011 and 2012. After 2011, no schistosome infected snails were found.

CONCLUSIONS

The schistosome infection rate of population has been controlled at a low level in Tongling County, but the snail area is still large in the marshland and lake regions, and the density of living snails is relatively high in the inland. Therefore, the schistosomiasis control work, especially snail control, still should be strengthened.

[Effect of schistosomiasis control in towns reached criteria of infection controlled in Nanchang City]

OBJECTIVE

To evaluate the effect of schistosomiasis control in towns that had reached the criteria of infection controlled in Nanchang City.

METHODS

The residents and livestock of 14 towns that had reached the criteria of infection controlled in Nanchang, Xinjian and Jinxian counties of Nanchang City were sampled to investigate the schistosomiasis endemic situation, Oncomelania hupensis snail status, and data of schistosomiasis control work.

RESULTS

The positive rate of serum tests of the residents was 2.58%, and no positive stool samples were found. No cattle or sheep were positive in stool tests. Totally 1 635 snails were caught, and 1278 were alive with an average density of living snails of 0.051/0.1 M2, while no schistosome infected snails were found. All the surveyed administrative villages had the completed files of schistosomiasis control. Conclusion All the 14 towns that had reached the criteria of infection controlled of schistosomiasis have already reached the criteria of transmission controlled in Nanchang City.

Hepatitis B virus: Where do we stand and what is the next step for eradication?

Hepatitis B (HB) virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980s. The World Health Organization recommended the integration of the HB vaccine into the national immunisation programs in all countries. HBV prevention strategies are classified into three groups: (1) universal vaccination alone; (2) universal vaccination with screening of pregnant women plus HB immune globulin (HBIG) at birth; and (3) selective vaccination with screening of pregnant women plus HBIG at birth. Most low-income countries have adopted universal vaccine programs without screening of pregnant women. However, HB vaccines are not widely used in low-income countries. The Global Alliance for Vaccine and Immunization was launched in 2000, and by 2012, the global coverage of a three-dose HB vaccine had increased to 79%. The next challenges are to further increase the coverage rate, close the gap between recommendations and routine practices, approach high-risk individuals, screen and treat chronically infected individuals, and prevent breakthrough infections. To eradicate HBV infections, strenuous efforts are required to overcome socioeconomic barriers to the HB vaccine; this task is expected to take several decades to complete.

Towards elimination of lymphatic filariasis: social mobilization issues and challenges in mass drug administration with anti-filarial drugs in Tamil Nadu, South India

India is a signatory to World Health Assembly resolution for elimination of lymphatic filariasis (LF) and National Health Policy has set the goal of LF elimination by 2015. Annual mass drug administration (MDA) is ongoing in endemic districts since 1996-97. Compliance rate is a crucial factor in achieving elimination and was assessed in three districts of Tamil Nadu for 10th and 11th treatment rounds (TRs). An in-depth study assessed the impact of social mobilization by drug distributors (DDs) in two areas from each of the three districts. Overall coverage and compliance for assessed TRs were 76.3 and 67.7% which is below the optimum level to achieve LF elimination. Modifiable determinants continue to be the reason for non-consumption even in the 11th TR and 20.8% were systematic non-compliers. In 76.4% of the cases, DDs failed to adhere to three mandatory visits as per the guidelines. Number of visits by DDs in relation to low and high MDA coverage areas showed a significant relationship (P ≤ 0.000). MDA is limited to drug distribution alone and efforts by DDs in preparing the community were inadequate. Probable means to meet the challenges in preparation of the community is discussed.

[Study on assessing system for endemicity of schistosomiasis]

OBJECTIVE

To establish a scientific, objective and operational assessing system for schistosomiasis endemicity, so as to provide a scientific evidence for revising the current Criteria for Control and Elimination of Schistosomiasis in China (GB 15976-2006).

METHODS

A questionnaire was designed based on reference review and 20 scientists working in the field of schistosomiasis control, research or management were investigated by using the Delphi method. The importance of each index reflecting the endemicity of schistosomiasis was scored by each scientist. The assessing system for endemicity of schistosomiasis was established and the normalized weight and combined weight were calculated.

RESULTS

The assessing system included three indices in the first grade and seven indices in the second grade. Among the indices in the first grade, the normalized weights of infection status of human beings, infection status of livestock, and Oncomelania snail's status were 0.360 2, 0.335 2, and 0.304 6, respectively. Among the indices in the second grade, the prevalence of livestock showed the highest combined weight of 0.335 2 while the infection rate of snails showed the lowest score of 0.093 3.

CONCLUSIONS

The indexes of the assessing system for the endemicity of schistosomiasis established are reasonable, comprehensive, and authoritative, which provide the scientific evidence for revising the currently available Criteria for Control and Elimination of Schistosomiasis in China.

[Role of the new version of the Control and Elimination Criteria for Schistosomiasis in acceleration of the schistosomiasis elimination program in China]

Based on the historical background for revision of the Control and Elimination Criteria for Schistosomiasis for 6 times, and the role of the criteria in promotion of national schistosomiasis control program of China at various stages, the present study demonstrated the necessity of further revision of the control criteria in the current schistosomiasis elimination program. In addition, the background for revision of the novel version of the Control and Elimination Criteria for Schistosomiasis was illustrated based on literature review, retrospective survey, expert argumentation and index improvement.