A case of group infections with Paraginimus species in Henan, Central China.

In July of 2012, mass infections with Paragonimus species were detected in the Henan province sickening 11 of 51 people. In May 2011, these individuals had participated in an excursion during which freshwater crabs were caught and served after being toasted. Before the group infections with Paraginimus species was confirmed, 5 of the 11 patients had been misdiagnosed as tuberculosis (TB) and treated with an anti-TB drug regimen for six months. The most common and typical manifestations were eosinophilia (11/11, 100%) and pulmonary manifestations including, among others, stethalgia and cough (7/11 63.6%). Sero-examination revealed that all 11 patients were seropositive for Paragonimus species. Surprisingly, in our case, one patient presented with hemoptysis and eggs in respiratory secretions, and this is the first time P. skrjabini eggs are detected in the sputum of a patient from the Henan province. Paragonimus metacercariae were collected from 6 of 11 (54.5%) crabs caught at the infection site and were identified as Paraginiumus skrjabini by morphological and molecular examinations. Epidemiological and laboratory evidence confirmed that this is a case of group infection with P. skrjabini. As one of the most neglected tropical diseases (NTD), paragonimiasis should be differentiated diagnosed from TB to avoid the delay of treatment. To our knowledge, this is the second report of a case of group infections with Paraginimus species in Henan, Central China. The first case was reported in 1995. As a kind of food-borne parasitic disease, paragonimiasis should be included in the public health education agenda.

Prevalence of severe fever with thrombocytopenia syndrome virus in animals in Henan Province, China.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). SFTSV has been found in humans, ticks and animals, and SFTS has high mortality and increasing prevalence in East Asia. In the study, the samples (heart, liver, lung, kidney, spleen, brain tissue and serum) were collected from 374 domestic animals and 241 wild animals in Pingqiao District and Xinxian County of Xinyang in Henan Province, China. 275 (44.72%, 275/615) animals were positive for anti-SFTSV antibodies, the anti-SFTSV antibodies positive ratios of domestic and wild animals were 43.58% (163/374) and 46.47% (112/241), respectively. There was no significant difference in domestic and wild animals, but significant differences were detected among different species of animals (χ2 = 112.59, P < 0.0001). Among 615 animals, 105 (17.07%, 105/615) animals were positive for SFTSV RNA, and only one SFTSV strain was isolated from heart tissue of a yellow weasel. The phylogenetic analysis shows that the sequence from animals belonged to the same group with viral sequences obtained from humans. The animals maybe play a reservoir host in maintaining the life cycle of SFTSV in nature.

Distribution of Avian Influenza A Viruses in Poultry-Related Environment and Its Association with Human Infection in Henan, 2016 to 2017.

OBJECTIVE: To survey avian influenza A viruses (AIVs) in the environment and explore the reasons for the surge in human H7N9 cases. METHODS: A total of 1,045 samples were collected from routine surveillance on poultry-related environments and 307 samples from human H7N9 cases-exposed environments in Henan from 2016 to 2017. The nucleic acids of influenza A (Flu A), H5, H7, and H9 subtypes were detected by real-time polymerase chain reaction. RESULTS: A total of 27 H7N9 cases were confirmed in Henan from 2016 to 2017, 24 had a history of live poultry exposure, and 15 had H7N9 virus detected in the related live poultry markets (LPMs). About 96% (264/275) Flu A positive-environmental samples were from LPMs. H9 was the main AIV subtype (10.05%) from routine surveillance sites with only 1 H7-positive sample, whereas 21.17% samples were H7-positive in H7N9 cases-exposed environments. Samples from H7N9 cases-exposed LPMs (47.56%) had much higher AIVs positive rates than those from routine surveillance sites (12.34%). The H7+H9 combination of mixed infection was 78.18% (43/55) of H7-positive samples and 41.34% (43/104) of H9-positive samples. CONCLUSION: The contamination status of AIVs in poultry-related environments is closely associated with the incidence of human infection caused by AIVs. Therefore, systematic surveillance of AIVs in LPMs in China is essential for the detection of novel reassortant viruses and their potential for interspecies transmission.

Chinese guidelines for the diagnosis and treatment of hand, foot and mouth disease (2018 edition).

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awareness and effective treatments, to further standardize and strengthen the clinical management and to reduce the mortality of HFMD, the guidelines for diagnosis and treatment have been developed. METHODS: National Health Commission of China assembled an expert committee for a revision of the guidelines. The committee included 33 members who are specialized in diagnosis and treatment of HFMD. RESULTS: Early recognition of severe cases is utmost important in diagnosis and treatment of patients with HFMD. The key to diagnosis and treatment of severe cases lies in the timely and accurate recognition of stages 2 and 3 of HFMD, in order to stop progression to stage 4. Clinicians should particularly pay attention to those EV-A71 cases in children aged less than 3 years, and those with disease duration less than 3 days. The following indicators should alert the clinician of possible deterioration and impending critical disease: (1) persistent hyperthermia; (2) involvement of nervous system; (3) worsening respiratory rate and rhythm; (4) circulatory dysfunction; (5) elevated peripheral WBC count; (6) elevated blood glucose and (7) elevated blood lactic acid. For treatment, most mild cases can be treated as outpatients. Patients should be isolated to avoid cross-infection. Intense treatment modalities should be given for those severe cases. CONCLUSION: The guidelines can provide systematic guidance on the diagnosis and management of HFMD.

Analysis of polymorphisms in the circumsporozoite protein gene of Plasmodium vivax isolates from Henan Province, China.

BACKGROUND: Plasmodium vivax malaria has historically been a major source of disease in Henan, China. In the 1970s, the morbidity of malaria was highest in the country. With support from the government and the efforts of healthcare personnel, the reported malaria cases have declined dramatically and a national elimination programme was launched in 2010. To achieve the goal, it is essential to study the diversity of autochthonous malaria and transmission of Plasmodium parasites, which will provide baseline data for disease control and management. METHODS: Thirty-two P. vivax isolates from Henan province were collected from 2008 to 2011, and circumsporozoite protein (csp) genes were analysed to estimate the genetic diversity of this parasite. RESULTS: The assessment of csp sequences indicated that all the isolates were the VK210 type, however, none of them was identical to the VK210 strain. The sequences displayed variations in the central region, and eight sub-types were observed. Among the sub-types, HN7 was the most prevalent (37.5%), followed by HN3 (34.4%). A total of 653 repeat units were discovered in 32 Henan isolates. Nucleotide sequences were grouped in 13 unique repeat nucleotide sequence allotypes that coded for 7 different repeated amino acid allotypes. B (GNGAGGQAA) and D (GDRAAGQPA) were more frequent based on the results; they represented 53.9% (352/653) of the total. In comparison to the basic repeat units of VK210, more than 75% of the central repeat units had at least one non-synonymous nucleotide change. CONCLUSIONS: Recent P. vivax populations in Henan province showed some degree of genetic diversity in csp, with 8 sub-types among 32 samples. Meantime, the results also suggested its relative conserved parasite populations. This could provide interesting baseline data that allow identifying whether potential new cases differ from the parasites already circulating in the area.

Bites from the same dog, different outcomes for two patients: a case report.

BACKGROUND: Rabies is a serious reemerging zoonosis in China. At present human rabies cases are primarily diagnosed based on clinical presentation. CASE PRESENTATION: In August 2012, a woman and her son were attacked by a stray dog in Henan, China. The son received rabies postexposure prophylaxis (wound treatment followed by vaccine, no immunoglobulin), however, the mother did not. Rabies infection was subsequently laboratory confirmed in the mother and she died in December; her son is alive and healthy after 2 years of follow-up. CONCLUSION: This report documents that the timely utilization of postexposure prophylaxis is a required measure in preventing rabies after exposure to an animal bite.

Prolonged parasite clearance in a Chinese splenectomized patient with falciparum malaria imported from Nigeria.

BACKGROUND: The spleen plays a pivotal role in the rapid clearance of parasitized red blood cells in patients with falciparum malaria after artemisinin treatment. Prolonged parasite clearance can be found in patients who have had a splenectomy, or those with hemoglobin abnormalities and/or reduced immunity, which are all distinguishable from artemisinin resistance. This paper reports on a case of prolonged parasite clearance in a Chinese splenectomized patient with falciparum malaria imported from Nigeria. CASE PRESENTATION: A 35-year-old Chinese male suffered 2 days of febrile illness after returning to Zhumadian city of Henan province from Nigeria on October 1, 2014. The main symptoms were febrile, including the highest axillary temperature of 40 °C, headache, and chills. A peripheral blood smear showed parasitemia (53 913 asexual parasites/µl) of Plasmodium falciparum. The patient had not used any chemoprophylaxis against malaria in Nigeria when he worked there as a construction worker between 2009 and 2014. The patient had three episodes of malaria in Nigeria and had a splenectomy due to a traffic accident 8 years ago from the time he was admitted to hospital. The patient was orally administrated a total of 320 mg/2.56 g dihydroartemisinin-piperaquine for 2 days and intravenously administrated a total of 3 000 mg artesunate for 18 days. The axillary temperature of the patient ranged between 37.0 and 37.7 °C from Day 0 to Day 3, and blood microscopy revealed falciparum malaria parasitemia (26 674 asexual parasites/µl) on Day 3. The patient was afebrile on Day 4, falciparum malaria parasitemia was continuously present and then gradually decreased on the next days, and was negative on Day 21. The patient was cured and left hospital on Day 24 after no plasmodium falciparum was found in the blood on Day 21 to Day 23. No mutation was found in the K13 propeller gene when compared with the PF3D7_1343700 K13 propeller gene reference sequence. CONCLUSIONS: This is the first reported case in China of prolonged parasite clearance in a splenectomized patient with imported falciparum malaria. Artemisinin resistance should be distinguished when prolonged parasite clearance is found in a malaria patient who has had splenectomy.

A large outbreak of acute gastroenteritis caused by the human norovirus GII.17 strain at a university in Henan Province, China.

BACKGROUND: Human noroviruses are a major cause of viral gastroenteritis and are the main etiological agents of acute gastroenteritis outbreaks. An increasing number of outbreaks and sporadic cases of norovirus have been reported in China in recent years. There was a large acute gastroenteritis outbreak at a university in Henan Province, China in the past five years. We want to identify the source, transmission routes of the outbreak by epidemiological investigation and laboratory testing in order to provide the effective control measures. METHODS: The clinical cases were investigated, and analysed by descriptive epidemiological methods according to factors such as time, department, grade and so on. Samples were collected from clinical cases, healthy persons, the environment, water, and food at the university. These samples were tested for potential bacteria and viruses. The samples that tested positive for norovirus were selected for whole genome sequencing and the sequences were then analysed. RESULTS: From 4 March to 3 April 2015, a total of 753 acute diarrhoea cases were reported at the university; the attack rate was 3.29%. The epidemic curve showed two peaks, with the main peak occurring between 10 and 20 March, accounting for 85.26% of reported cases. The rates of norovirus detection in samples from confirmed cases, people without symptoms, and environmental samples were 32.72%, 17.39%, and 9.17%, respectively. The phylogenetic analysis showed that the norovirus belonged to the genotype GII.17. CONCLUSIONS: This is the largest and most severe outbreak caused by genotype GII.17 norovirus in recent years in China. The GII.17 viruses displayed high epidemic activity and have become a dominant strain in China since the winter of 2014, having replaced the previously dominant GII.4 Sydney 2012 strain.

[Polymorphisms of tryptophan-rich antigen gene of Plasmodium ovale subspecies from imported malaria cases in Henan Province].

Objective: To analyze the genetic sequence of tryptophan-rich antigen (PoTRA) gene of Plasmodium ovale subspecies from imported malaria cases in Henan Province in 2015. Methods: Blood samples were collected from 22 imported ovale malaria cases in Henan Province in 2015. After DNA extraction, PoTRA was amplified by nested PCR, and was inserted into the pMD18-T vector. The plasmid was extracted and sequenced, and the results were blasted in GenBank to determine the subspecies of P. ovale. The sizes and species of the PoTRA gene were analyzed. The amino-acid sequence of PoTRA was also aligned to analyze the difference in amino acid sequence. The phylogenetic tree was constructed to analyze the genetic relationship among the samples by neighbor-joining. Results: Of the 22 imported cases, eight (36.4%) were infected with P. ovale wallikeri, which had two sizes, the predominant 245 and 299 bp. The other 14 cases (63.6%) were infected with P. ovale curtisi, which had three sizes, the predominant 299, 317 and 335 bp. Amino-acid sequence alignment revealed that the two types of P. ovale wallikeri differed in two amino-acid units, MANPINMANPIN and AITPIN, while the three types of P. ovale curtisi differed in amino-acid units TITPIS and TINPIN. The phylogenetic tree showed that the 22 samples belonged to two subpopulations of P. ovale curtisi and P. ovale wallikeri, wherein the P. ovale curtisi was further divided into two sub-branches, and samples with sizes of 317 and 335 bp were in the same sub-branch with a closer genetic relationship. Conclusion: Two subspecies, P. ovale curtisi and P. ovale wallikeri, are identified from the imported ovale malaria cases in Henan Province in 2015. The P. ovale curtisi has three genetic types and P. ovale wallikeri has two genetic types of PoTRA gene, revealing genetic polymorphisms of PoTRA.

Molecular mutation profile of pfcrt in Plasmodium falciparum isolates imported from Africa in Henan province.

BACKGROUND: Anti-malarial drug resistance is a primary public health problem. Haplotypes of pfcrt gene have been implicated to be molecular markers of chloroquine (CQ) resistance. This study aims to explore the prevalence of polymorphisms in pfcrt in Plasmodium falciparum-infected patients imported from Africa in Henan province. METHODS: Blood samples were collected from 502 patients who were infected with P. falciparum returning from Africa in Henan province during 2012-2015. The single nucleotide polymorphisms in pfcrt (codons 72-76) were assessed by nested PCR with DNA sequencing and restriction digestion, the haplotype prevalences were also determined. RESULTS: Four haplotypes coding 72-76 of pfcrt were found including CVMNK (wild type), CVIET (mutation type), CVIEK (mutation type), and CV M/I N/E/D/K K/T (mixed type), with 61.95 % (311/502), 33.07 % (166/502), 0.20 % (1/502), and 4.78 % (24/502) prevalence, respectively. Except mixed type, CVIET and CVIEK were the largest proportion of the mutant type in West Africa, accounting for 44.83 % (91/203), followed by East Africa (8/21, 38.10 %), North Africa (4/11, 36.36 %), Central Africa (36/135, 26.67 %), and South Africa (28/132, 21.21 %). There was significant difference among the groups (χ(2) = 23.78, P < 0.05). Mixed type was the largest proportion in North Africa (9.09 %), followed by Central Africa (6.67 %), East Africa (4.76 %), South Africa (4.55 %), and West Africa (3.45 %). There was no significant difference among the groups (χ(2) = 2.31, P > 0.05). The position 72 and 73 of pfcrt showed predominance for the wild type with rates of 100 % (502/502). CONCLUSIONS: This study identified four haplotypes of pfcrt in P. falciparum-infected patients imported from Africa in Henan province. The prevalence of mutations in the pfcrt was dropped comparing with other people's researches. It establishes fundamental data for detection of P. falciparum CQR with molecular markers for the imported P. falciparum in China, and it also provides complementary information of CQR for the malaria endemic countries and assesses the evolution of anti-malarial drug resistance.

[Medical Costs on Malaria in Henan Province and Analysis of the Influential Factors].

Objective: To analyze the costs for the diagnosis and treatment of malaria in Henan Province and the influential factors. Methods: Malaria cases diagnosed in and reported by medical institutions in Henan Province from November 2013 to October 2014 were selected. General information and clinical information of those with further microscopic confirmation were also collected. The rank sum test for two or more independent samples and stepwise regression analysis were used to investigate the influential factors for medical costs. Results: A total of 218 malaria cases were finally included, of whom 73.4% were from rural areas. On average, the medical costs for patients from rural areas and cities/towns were 1 503 yuan and 4 833 yuan respectively. The average medical cost per patient with first-visit in rural hospitals was 2 600 yuan, and that with first-visit in provincial hospitals was 7 800 yuan. The average medical costs for patients diagnosed in county/city-level hospitals and provincial hospitals were 1 022.5 yuan and 6 170 yuan, respectively. There was null cost for patients diagnosed at the first-visit, while for those diagnosed after 3 or more visits the average cost per patient was 5 621 yuan. Factors significantly associated with medical costs were the current living locality of patients, the hospital level of first-visit, the hospital level of diagnosis and the number of visits before diagnosis（P＜0.05）. Stepwise regression analysis showed that the hospital level of first-visit was the most important influential factor for medical cost, followed by the hospital level of diagnosis and the number of visits before diagnosis. The higher hospital levels of first-visit and diagnosis, the higher cost. The same applied to the number of visits before diagnosis. Conclusion: There is an considerable correlation between medical cost and health seeking behavior in malaria patients.

[Analysis of Pfcrt Gene Polymorphism in Imported Falciparum Malaria Cases in Henan Province in 2015].

Objective: To analyze Plasmodium falciparum chloroquine resistant transporter (Pfcrt) gene polymorphism in imported falciparum malaria cases in Henan Province in 2015. Methods: Blood samples were collected from 132 cases of imported falciparum malaria in Henan Province in 2015. DNA was extracted from the samples, and the Pfcrt was amplified by nested PCR using specific primers. The PCR products were digested by restriction endonuclease enzyme Apol I and sequenced. Pfcrt gene polymorphism and distribution were analyzed. Results: Most of the 132 cases of imported malaria were young male adults returning from the Africa, with the highest percentage in those from West Africa（38.6%, 51/132）, then Central Africa（26.5%, 35/132）, South Africa（25.0%, 33/132）, East Africa（8.3%, 11/132）, and North Africa（1.5%, 2/132）. The nested PCR yielded a 145-bp product for each sample, and 66.7%（88/132） of the products were completely digested by Apol I, resulting in two fragments of 114 bp and 31 bp; 32.6%（43/132） could not been digested and only a single fragment of 145 bp was shown; and 0.8%（1/132） were incompletely digested, yielding three fragments of 145 bp, 114 bp and 31 bp. By blasting against chloroquine sensitive strain 3D7, we found mutations of Pfcrt at sites correspondig to residues 74, 75 and 76 from ATG, AAT and AAA to ATT, GAA and ACA （i.e. M74I, N75E and K76T） in 43 of the 132 blood samples, and mixed type mutations into ATG/T, A/GAA/T and AA/CA at sites correspondig to residues 74, 75 and 76（CVM/I, N/E/D/K, T/K） in one blood sample. The other 88 blood samples showed a wild type with no mutation (CVMNK). Mutations occurred mainly in cases from West Africa（41.2%, 21/51）, then East Africa（36.4%, 4/11）, South Africa（30.3%, 10/33）, and Central Africa（22.9%, 8/27）（χ2=4.07, P＞0.05）. The 2 cases from the North Africa both had wild type Pfcrt; the one with mixed type mutation was from West Africa. Conclusion: Three haplotypes of Pfcrt have been found, including wild type (CVMNK), mutation type (CVIET) and mixed type (CVM/I, N/E/D/K, K/T) in the imported malaria cases. The wild type occupies the highest proportion （66.7%）, while the mutation type possesses a high proportion of 41.2% in cases from West Africa.

[Results of Soil-transmitted Nematode Monitoring in Henan Province in 2011-2015].

To understand the endemic situation of soil-transmitted nematodiasis (Ascaris lumbricoides, Trichuris trichiura and Ancylostoma sp.) in Huaiyang County, Henan Province. Over 1 000 fecal samples from inhabitants in Huaiyang County of Henan Province were collected each year during 2011-2015, in which the soil-transmitted nematodes eggs and other intestinal helminth eggs were examined by Kato-Katz technique. The helminth-positive samples were examined by filter paper culture method to identify the species of hookworm. The cellophane swab method was used to detect Enterobius vermicularis eggs in children aged 3～12 years. Soil samples were collected from vegetable field, lavatory, courtyard and kitchen of 10 families randomly selected in each year to examine Ascaris eggs by a modified saturated sodium nitrate floatation method. In 2011-2015, 5 229 people were examined and 54 person infected with intestinal helminths were found. Five intestinal helminthes, A. lumbricoides, T. trichiura, Ancylostoma duodenale, Enterobius vermicularis and Trichostrongylus orientalis were found with 13, 2, 9, 29 and 1 infection person respectively. All showed mild infection and no multiple infections were found. There was no significant difference between the year 2015 which had the highest soil-transmitted nematode infection rate 0.6%（7/1 134） and the year 2013 which had the lowest infection rate 0.3%（3/1 037）（P>0.05）. The infection rate of intestinal helminths was highest in group of <10 years（2.8%, 25/905）, followed by the groups of >70 years（1.6%, 4/256） and 30～40 years（1.2%, 8/671）（P>0.05）. The average infection rate of E. vermicularis was 1.8%（18/993） The infection rate of E. vermicularis was relatively higher in kindergarten kids（1.6%, 6/366） and students（1.3%, 13/1 005） than that in farmers（0.3%, 10/3 782）（P<0.01）. No Ascaris eggs were found in the 200 randomly collected soil samples. The intestinal helminth infection status maintaines at low level in Henan Province during 2011-2015.

[Tracing Investigation of One Vivax Malaria Case by Detecting the Gene Encoding Circumsporozoite Protein in Henan].

A vivax malaria case in Henan Province was diagnosed as an indigenous case firstly in June 2013, and replased in April 2014. The clinical data of this case were collected and the epidemiological investigation was conducted. The blood samples were examined by Giemsa-stained blood smear, rapid diagnostic test strip (RDT) and nested PCR. This patient stayed at Myanmar for about one week in May 2013, had the symptoms of chills, fever and sweating in June, and was diagnosed as vivax malaria. After treated with artesunate, the symptoms disappeared. The CSP sequence was amplified from the blood samples of the first and second attack, and there was no difference in the central repeat domain of CSP gene. The identity of our two CSP gene sequences to that of Myanmar isolates (GenBank accessssion No. ABS95455, ABS95456) was 95.1% and 100%, while their nucleotide sequence was with 88.8% and 67.1% identity with that of Henan isolates (accessssion No. KP888996, KP889000), respectively. This patient is therefore confirmed as an imported relapse case of Plasmodium vivax infection.

Prevalence and risk factors of intestinal protozoan and helminth infections among pulmonary tuberculosis patients without HIV infection in a rural county in P. R. China.

Although co-infection of tuberculosis (TB) and intestinal parasites, including protozoa and helminths, in humans has been widely studied globally, very little of this phenomenon is known in China. Therefore, a cross-sectional study was conducted in a rural county of China to investigate such co-infections. Patients with pulmonary TB (PTB) undergoing anti-Mycobacterium tuberculosis (anti-MTB) treatment were surveyed by questionnaires, and their feces and blood specimens were collected for detection of intestinal protozoa and helminths, routine blood examination and HIV detection. The χ(2) test and multivariate logistic regression model were used to identify risk factors. A total of 369 patients with PTB were included and all of them were HIV negative. Overall, only 7.3% of participants were infected with intestinal protozoa, among which prevalence of Blastocystis hominis, Entamoeba spp. and Trichomonas hominis were 6.0%, 1.1% and 0.3%, respectively; 7.0% were infected with intestinal helminths, among which prevalence of hookworm, Trichuris trichiura, Ascaris lumbricoides and Clonorchis sinensis were 4.3%, 1.9%, 0.5% and 0.3%, respectively; and 0.5% were simultaneously infected with intestinal protozoa and helminths. Among patients with PTB, body mass index (BMI)≤18 (OR=3.30, 95% CI=1.44-7.54) and raised poultry or livestock (e.g., chicken, duck, pig) (OR=3.96, 95% CI=1.32-11.89) were significantly associated with harboring intestinal protozoan infection, while BMI≤18 (OR=3.32, 95% CI=1.39-7.91), anemia (OR=3.40, 95% CI=1.44-8.02) and laboring barefoot in farmlands (OR=4.54, 95% CI=1.88-10.92) were significantly associated with having intestinal helminth infection. Additionally, there was no significant relationship between duration of anti-MTB treatment and infection rates of intestinal parasites including protozoa and helminths. Therefore, preventing malnutrition, avoiding unprotected contact with reservoirs of protozoa, and improving health education for good hygiene habits, particularly wearing shoes while outdoors, are beneficial in the prevention of intestinal protozoan and helminth infection among patients with PTB.

Knockdown resistance of Anopheles sinensis in Henan province, China.

BACKGROUND: Vivax malaria was historically epidemic in Henan Province of China and Anopheles sinensis was the main vectors and poor farming communities bare the greatest burden of disease. Knockdown resistance in An. sinensis is one of the mechanisms of resistance against pyrethroids. In the present study, the frequency of mutations from An. sinensis was examined in Henan province, China. METHODS: Anopheles was collected from Kaifeng, Tongbai, Tanghe, Pingqiao, Shihe, and Yongcheng counties of Henan province in 2013. Molecular identification of Anopheles species was conducted by polymerase chain reaction (PCR) amplifying the internal transcribed spacer 2 (ITS2). Part of the IIS6 domain of the para-type sodium channel protein gene was polymerase chain reaction-amplified and directly sequenced. Frequency and geographic difference of kdr gene mutant types were analysed. RESULTS: 208 Anopheles were received molecular identification, of which 169 (81.25%) were An. sinensis, 25 (12.02%) were Anopheles yatsushiroensis, and 12 (5.77%) were Anopheles lesteri. A 325 bp fragment of the para-type sodium channel gene including position 1014 was successfully sequenced from 139 Anopheles, of which 125 (89.93%) were An. sinensis, 12 (8.63%) were An. yatsushiroensis, 2 (1.44%) were An. lesteri. The molecular analyses revealed that mutations existed at codon 1014 in An. sinensis but not in An. yatsushiroensis and An. lesteri. Frequency of kdr mutation was 73.60% (92/125) from population of An. sinensis in Henan province, of which L1014F (TTT + TTC) allele frequencies accounted for 46.40% (58/125), and was higher than that of L1014C(TGT) which accounted for 27.20% (34/125) ( χ2 = 55.423, P < 0.001). The frequency of kdr mutation in Kaifeng county was 100% (49/49), and was higher than that of 37.93% (11/29) in Tongbai, 54.55% (6/11) in Pingqiao, 50.00% (3/3) in Shihe, and 62.50% (10/16) in Yongcheng county, respectively (χ2 = 39.538, P < 0.001; χ2 = 24.298, P < 0.001; χ2 = 25.913, P < 0.001; χ2 = 20.244, P < 0.001). While 92.86% (13/14) frequency of kdr mutation was found in Tanghe county, which was higher than that in Tongbai county (χ2 = 11.550, P = 0.0018). CONCLUSIONS: A high frequency of kdr gene mutations from population of An. sinensis in Henan province was found.

Preparation of malaria resurgence in China: case study of vivax malaria re-emergence and outbreak in Huang-Huai Plain in 2006.

This chapter reviews the patterns of malaria re-emergence and outbreak that occurred in the Huang-Huai Plain of China in 2006, and the way of quick response to curtail the outbreak by mass drug administration and case management. The contribution of the each intervention in quick response is discussed. Particularly due to the special ecological characteristics in the Huang-Huai Plain, the intervention of vector control is not implemented. Finally, the challenges in the elimination of malaria in this region are highlighted.

Outbreak of dengue Fever in central China, 2013.

In 2013, the first dengue fever (DF) outbreak in central China was reported in the central of Henan province, northern temperate regions, although they have been sequentially recorded in Southern China. 106 suspected DF cases were reported and 73 patients were confirmed dengue virus type 3 (DEN-3) infections. 62/392 (15.8%) local health persons showed DEN antibodies positive. To this day Henan is the northernmost province in China which has been reported about outbreak of DF and what is important is that it warns us the endemic range of DF has been expanded geographically in China.

First imported relapse case of Plasmodium vivax malaria and analysis of its origin by CSP sequencing in Henan Province, China.

In recent years, there has been a substantial increase of imported Plasmodium vivax incidence in Henan Province. As China is in a pre-elimination phase, the surveillance of imported malaria is essential, but there is no good way to distinguish imported cases from indigenous cases. This paper reports a case of a 39-year-old man who acquired P. vivax while staying in Indonesia for one month in 2013, and relapsed in Henan, China in 2014. This was diagnosed as vivax malaria based on rapid diagnostic test, Giemsa-stained peripheral blood smear and Plasmodium species-specific nested PCR. The genetic sequence for the circumsporozoite protein genes was analysed and the genetic variations were compared with a previously constructed database of Chinese isolates. The results from the circumsporozoite protein (CSP) gene sequence analysis centered on the repeat patterns showed that the imported cases had completely different sequences from any subtypes from Chinese isolates, but well matched with the countries travelled by the patient. The imported vivax cases were able to clearly distinguish from the indigenous vivax cases by detecting the CSP gene and were able to confim its origin by genotyping.

Tick-borne pathogens and associated co-infections in ticks collected from domestic animals in central China.

BACKGROUND: Ticks can transmit a number of pathogens to humans and domestic animals. Tick borne diseases (TBDs), which may lead to organ failure and death have been recently reported in China. 98.75% of the total cases (>1000) in Henan provinces have been reported in Xinyang city. Therefore, the aims of this study were to investigate the fauna of ticks and detect the potential pathogens in ticks in Xinyang, the region of central China. METHODS: Ticks were collected from 10 villages of Xinyang from April to December 2012, from domestic animals including sheep, cattle and dogs. Then identification of ticks and detection of tick-borne pathogens, including Babesia spp., Theileria spp., Anaplasma spp., Ehrlichia spp., Rickettsia spp., tick-borne encephalitis virus (TBEV), Borrelia burgdorferi sensu lato, Leishmania infantum, were undertaken by using polymerase chain reaction assay (PCR) and sequence analysis. Moreover, the co-infection patterns of various pathogens were compared among locations where ticks were collected. RESULTS: A total of 308 ticks were collected. Two species of Ixodidae were found, namely Haemaphysalis longicornis (96.75%) and Rhipicephalus microplus (3.25%). Five genera of pathogens, namely Theileria spp. (3.25%), Anaplasma spp. (2.92%), Babesia spp. (1.95%), Ehrlichia spp. (2.92%) and Rickettsia spp. (0.65%), were detected in 7 villages. Co-infections by two pathogens were diagnosed in 11.11% of all infected ticks. CONCLUSIONS: Both human and animal pathogens were abundant in ticks in the study areas. Humans and animals in these regions were at a high risk of exposure to piroplasmosis, since piroplasm had the highest rates of infection and co-infection in positive ticks.