Application of Auto-regressive Linear Model in Understanding the Effect of Climate on Malaria Vectors Dynamics in the Three Gorges Reservoir

It is important to understand the dynamics of malaria vectors in implementing malaria control strategies. Six villages were selected from different sections in the Three Gorges Reservoir fc,r exploring the relationship between the climatic ｜：actors and its malaria vector density from 1997 to 2007 using the auto-regressive linear model regressi^n method. The result indicated that both temperature and precipitation were better modeled as quadratic rather than linearly related to the density of Anopheles sinensis.

The Identification of the Cryptosporidium ubiquitum in Pre-weaned Ovines from Aba Tibetan and Qiang Autonomous Prefecture in China

Objective Cryptosporidium spp. are prevalent globally and sheep are an important zoonotic reservoir. Little data regarding the rates of Cryptosporidium infections in ovines in China are available. This study assessed the prevalence of Cryptosporidium spp. in pre-weaned ovines from Aba Tibetan and Qiang Autonomous Prefecture in the Sichuan province of China. Methods A total of 213 fecal samples were collected from pre-weaned ovines and were examined microscopically （following modified acid fast staining）. In addition, 18S rRNA genetic sequences were amplified from fecal samples by nested PCR and phylogenetically analyzed. Results The prevalence of Cryptosporidium in the collected samples was at 14.6% （31/213） and four isolates identified by PCR belonged to the Cryptosporidium cervine genotype （Cryptosporidium ubiquiturn） demonstrating that this species was the primary sheep species found in sheep in China. Conclusion The present study suggested that the high incidence of Cryptosporidium in sheep poses a significant public health threat and that surveillance practices must be established to prevent zoonotic disease of humans.

Echinococcus Granulosus: Suitable in vitro Protoscolices Culture Density

The present study is to determine the suitable protoscolices （PSCs） density for long-time culturing in vitro. The PSCs were divided into eight groups with different densities and the viability tests were carried out with 0.1% methylene blue staining. Then the infection ability of cultured PSCs was assessed by the mean cyst weight of mice inoculated intraperitoneally with PSCs after 8 months post-infection.

Co-infections with Babesia microti and Plasmodium parasites along the China-Myanmar border

Background:Babesiosis is an emerging health risk in several parts of the world.However,little is known about the prevalence of Babesia in malaria-endemic countries.The area along the China-Myanmar border in Yunnan is a main endemic area of malaria in P.R.China,however,human infection with Babesia microti(B.microti)is not recognized in this region,and its profile of co-infection is not yet clear.Methods:To understand its profile of co-infections with B.microti,our investigation was undertaken in the malaria-endemic area along the China-Myanmar border in Yunnan between April 2012 and June 2013.Four parasite species,including B.microti,Plasmodium falciparum(P.falciparum),P.vivax,and P.malariae,were identified among 449 suspected febrile persons detected by nested polymerase chain reaction(PCR)assay based on small subunit ribosomal ribonucleic acid(RNA)genes of B.microti and Plasmodium spp.Results:Of all the collected samples from febrile patients,mono-infection with B.microti,P.vivax,P.falciparum,and P.malariae accounted for 1.8%(8/449),9.8%(44/449),2.9%(13/449),and 0.2%(1/449),respectively.The rate of mixed infections of B.microti with P.falciparum or P.vivax are both 0.2%(1/449),and mixed infections of P.falciparum and P.vivax accounted for 1.1%(5/449).Conclusions:This report supports the hypothesis that babesiosis caused by B.microti is emerging along the China-Myanmar border in the Yunnan province,P.R.China,but it was ignored because of low parasitemia or mixed infection with Plasmodium spp.More sensitive and specific diagnosis methods are needed to find the rapid response mechanism of emergency for babesiosis and malaria co-prevalence areas.

Elimination of tropical disease through surveillance and response

Surveillance and response represent the final crucial steps in achieving effective control and particularly elimination of communicable diseases as recognized in the area of neglected tropical diseases(NTDs),applied in increasing numbers in endemic countries with ongoing control and elimination programmers.More and more national NTD elimination initiatives are scheduled based on the innovative and effective One world-One health perspective to detect pockets of transmission and disease reintroduction.Resource-constrained countries,which carry the heaviest NTD burdens,face various challenges how to strengthen the health system as well as developing effective and novel tools for sureillance and response tailored to local settings.Surillance-response approaches take place in two different stages oralling the basic components of the sureillance response system for NTD elimination.Six different research priorities have been identified:(1)dynamic mapping of transmission,(2)near real-time capture of population dynamics,(3)modelling based on a minimum essential database/dataset,(4)implementation of mobile health(m-health)and sensitive diagnostics,(5)design of effective response packages tailored to different transmission settings and levels,and( 6)validation of approaches and responses packages.

Surveillance-response systems: the key to elimination of tropical diseases

Tropical diseases remain a major cause of morbidity and mortality in developing countries.Although combined health efforts brought about significant improvements over the past 20 years,communities in resource-constrained settings lack the means of strengthening their environment in directions that would provide less favourable conditions for pathogens.Still,the impact of infectious diseases is declining worldwide along with progress made regarding responses to basic health problems and improving health services delivery to the most vulnerable populations.The London Declaration on Neglected Tropical Diseases(NTDs),initiated by the World Health Organization’s NTD roadmap,set out the path towards control and eventual elimination of several tropical diseases by 2020,providing an impetus for local and regional disease elimination programmes.Tropical diseases are often patchy and erratic,and there are differing priorities in resources-limited and endemic countries at various levels of their public health systems.In order to identify and prioritize strategic research on elimination of tropical diseases,the‘First Forum on Surveillance-Response System Leading to Tropical Diseases Elimination’was convened in Shanghai in June 2012.Current strategies and the NTD roadmap were reviewed,followed by discussions on how to identify and critically examine prevailing challenges and opportunities,including inter-sectoral collaboration and approaches for elimination of several infectious,tropical diseases.A priority research agenda within a‘One Health-One World’frame of global health was developed,including(i)the establishment of a platform for resource-sharing and effective surveillance-response systems for Asia Pacific and Africa with an initial focus on elimination of lymphatic filariasis,malaria and schistosomiasis;(ii)development of new strategies,tools and approaches,such as improved diagnostics and antimalarial therapies;(iii)rigorous validation of surveillance-response systems;and(iv)designing pilot studies to transfer Chinese experiences of successful surveillance-response systems to endemic countries with limited resources.

HIV and intestinal parasite co-infections among a Chinese population: an immunological profile

Background:Parasite infections often result in a switch of the human body’s predominant immune reaction from T-helper 1(Th1)-type to Th2-type.Hence,parasite infections are widely expected to accelerate the progression of human immunodeficiency virus(HIV)infections to acquired immunodeficiency syndrome(AIDS).In the People’s Republic of China,both parasitic diseases and AIDS are epidemic in certain rural areas,and co-infections are relatively common.However,no population-based studies have yet investigated the frequency of HIV and parasite co-infections,and its effects on immune responses.We studied(1)the immune status of an HIV-infected population,and(2)the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune system.Methods:A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative individuals.Questionnaires were administered to all participants to obtain information on sociodemographic characteristics,sanitation habits,family income,and recent clinical manifestations.Two consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+T-lymphocytes,respectively.Results:During the study period,79 HIV-infected individuals were not under highly active antiretroviral therapy(HAART)and were thus included in our analysis;the prevalence of intestinal helminth infections was 6.3%and that of protozoa was 22.8%.The most common protozoan infections were Blastocystis hominis(B.hominis)(13.9%)and Cryptosporidium spp.(10.1%).The prevalence of Cryptosporidium spp.in HIV-infected individuals was significantly higher than that in HIV negative individuals(P<0.05).Compared to the non-co-infected population,no significant difference was found for any of the measured immunological indicators(P>0.05).However,the following trends were observed:IFN-γlevels were lower,but the IL-4 level was higher,in the population co-infected with HIV and helminths.In the population co-infected with HIV and B.hominis,the IL-2 level was higher.The population co-infected with HIV and Cryptosporidium spp.had markedly lower CD4+T-lymphocyte counts.Conclusion:According to the immunologic profile, co-infection with helminths is disadvantageous to HIV-infected individuals. It was associated with a shift in the Th1/Th2 balance in the same direction as that caused by the virus itself, which might indicate an acceleration of the progress from an HIV infection to AIDS. Co-infection with Cryptosporidium spp. was not associated with a significant change in immune factors but co-infection with Cryptosporidium spp. was associated with a reduced level of CD4 + T-lymphocytes, confirming the opportunistic nature of such infections. Co-infection with B. hominis, on the other hand, was associated with an antagonistic shift in the immunological profile compared to an HIV infection.

Acquired immunity and asymptomatic reservoir impact on frontline and airport ebola outbreak syndromic surveillance and response

The number of surveillance networks for infectious disease diagnosis and response has been growing.In 2000,the World Health Organization(WHO)established the Global Outbreak Alert and Response Network,which has been endorsed by each of the 46 WHO African members since then.Yet,taming the dynamics and plague of the vicious Ebola virus disease(EVD)in African countries has been patchy and erratic due to inadequate surveillance and contact tracing,community defiance and resistance,a lack of detection and response systems,meager/weak knowledge and information on the disease,inadequacies in protective materials protocols,contact tracing nightmare and differing priorities at various levels of the public health system.Despite the widespread acceptance of syndromic surveillance(SS)systems,their ability to provide early warning alerts and notifications of outbreaks is still unverified.Information is often too limited for any outbreak,or emerging or otherwise unexpected disease,to be recognized at either the community or the national level.Indeed,little is known about the role and the interactions between the Ebola infection and exposure to other syndemics and the development of acquired immunity,asymptomatic reservoir,and Ebola seroconversion.Can lessons be learnt from smallpox,polio,and influenza immunity,and can immunization against these serve as a guide?In most endemic countries,community health centers and disease control and prevention at airports solely relies on passive routine immunization control and reactive syndromic response.The frontline and airport Ebola SS systems in West Africa have shown deficiencies in terms of responding with an alarming number of case fatalities,and suggest that more detailed insights into Ebola,and proactive actions,are needed.The quest for effective early indicators(EEE)in shifting the public and global health paradigm requires the development and implementation of a comprehensive and effective community or regional integrated pandemic preparedness and surveillance response systems tailored to local contexts.These systems must have mechanisms for early identification,rapid contact tracing and tracking,confirmation,and communication with the local population and the global community,and must endeavor to respond in a timely manner.

EFFECT OF ANTIHYDATID DRUGS ON CARBOHYDRATE METABOLISM OF METACESTODE OF ECHINOCOCCUS GRANULOSUS

A biochemical some enzymes of glycolysis and a partial reversed tricarboxylic acid cycle together with hydrolytic enzymes in the cyst wall of Echinococcus granulosus was carried out. Lactate dehydrogenase (LDH), pyruvate kinase (PK), phosphoenolpyruvate carboxykinase (PEPCK), and adenosine triphosphatase (ATPase) showed their high level of activity, suggesting that the proliferation of E. granulosus cyst wall is an energy-dependent process and the major pathways for glucose metabolism is glycolysis. Treatment of E. granulosus-in-fected mice with mebendazole and albendazole resulted in marked inhibition of PK, PEPCK and ATPase of E. granulosus cyst wall, whereas praziquantel had no effect, indicating that PK, PEPCK, and ATPase might be chemotherapeutic targets and the differences in the inhibitory effects might account for the efficacy of the three antihydatid drugs.

Effects of the molluscicide can didate PPU06 on alkaline phosphatase in the golden apple snails determined using a near-infrared fluorescent probe

We constructed a reaction-based near-infrared fluorescent probe(Niap) to specifically identify alkaline phosphatase(ALP) with fast red fluorescence enhancement.Based on the positive concentrationdependent manner between the fluorescent intensity of the Niap and ALP,probe Niap was used to study the ALP enrichment and variation in golden apple snails(Pomacea canaliculata) exposed to the molluscicide candidate PPU06.After treatment with different concentrations of PPU06 over various times,three organs of the surviving snails,liver,stomach and plantaris,were frozen and sectioned for fluorescent imaging experiments.With increased PPU06 concentration,red fluorescence substantially increased in the liver and reached a maximum within 24 h when the PPU06 co ncentration was 0.75 mg/L.No obvious changes in the stomach or foot plantaris were found.It showed PPU06 caused liver injury and stimulated the increase of ALP in the liver of P.canaliculata.This study demonstrates a rapid ALP fluorescent identification method that can be used to study the effects of PPU06 on P.canaliculata.It also provides optical evidence that may aid in the discovery of new chemistry for snail control.

Profiling B and T cell immune responses to co-infection of Mycobacterium tuberculosis and hookworm in humans

Background:Humoral and cellular immune responses play protective roles against Mycobacterium tuberculosis(MTB)infection.However,hookworm infection decreases the immune response to hookworm and bystander antigens.Currently,immune responses to co-infection of MTB and hookworm are still unknown,although co-infection has been one of the public health problems in co-endemic areas of pulmonary tuberculosis(PTB)and hookworm disease.Therefore,it is essential to evaluate B and T cell immune responses to the co-infection.Methods:Seventeen PTB cases co-infected with hookworm,26 PTB cases,15 patients with hookworm infection,and 24 healthy controls without PTB or hookworm infection were enrolled in the study.Expressions of CD3,CD4,CD8,CD10,CD19,CD20,CD21,CD25,CD27,CD38,FoxP3,and PD-1 were assessed on B and T cell subsets using multicolor flow cytometry.Results:For the B cell(CD19+)subsets,naïve B cells(CD10−CD27−CD21+CD20+),plasma cells(CD10−CD27+CD21−CD20−),and tissue-like memory B cells(CD10−CD27−CD21−CD20+)had higher proportions,whilst resting memory B cells(CD10−CD27+CD21+CD20+)had lower proportions in the group co-infected with MTB and hookworm as compared to other groups.Frequencies of activated memory B cells(CD10−CD27+CD21−CD20+)did not differ among the four groups.For the T cell(CD3+)subsets,frequencies of regulatory T cells(CD4+CD25+Foxp3+)and exhausted CD4+and CD8+T cells(CD4+PD-1+and CD8+PD-1+)were higher,and frequencies of activated CD4+and CD8+T cells(CD4+CD38+and CD8+CD38+)were lower in the co-infected group as compared to the other groups.Conclusion:The change patterns of the cell profile of circulating lymphocytes were indentified in human co-infection of MTB and hookworm,which might indicate that the humoral and cellular immune responses are more suppressed.

Synthesis of 2,5-disubstitued benzimidazole using SnCl_2-catalyzed reduction system at room temperature

Stannous chloride dihydrate is used as an efficient catalyst in reductive cyclization of 2-nitro-5- substituted aniline Schiff base leading to stable 2,5-disubstitued benzimidazole derivatives in excellent yields with good purity. It provides a novel method of synthesis of 2,5-disubstitued benzimidazole under reductive system at room temperature.

Combating infectious diseases of poverty: a year on

The Infectious Diseases of Poverty journal,launched a year ago,is a platform to engage outside the traditional disciplinary boundaries,and disseminate high quality science towards the improvement of health.This paper reviews the milestone achievements during its first year of operation.The journal has filled an important niche,addressing some of the main priorities in the Global Report for Research on Infectious Diseases of Poverty.Highlights include the publication of three thematic issues on health systems,surveillance and response systems,as well as co-infection and syndemics.The thematic issues have foregrounded the importance and innovation that can be achieved through transdisciplinary research.The journal has been indexed by PubMed since April 2013,with the publication of a total of 38 articles.Finally,the journal is delivering to wider range readers both in developing and developed countries with sustained efforts with a focus on relevant and strategic information towards elimination of infectious diseases of poverty.