RESUMEN
Objective: To diagnose and treat the first imported active case of Plasmodium knowlesi infection in China. Methods: The clinical information of the patient was collected. Microscopy of blood smear was conducted after Giemsa staining. Genomic DNA was extracted from blood, and PCR was conducted to amplify rDNA. The PCR products were sequenced and analyzed with BLAST Results: The patient returned from a one-week tour in a tropical rain forest in Malaysia. The first disease attack occurred in Guangzhou on Oct. 16, 2014, with fever, shivering and sweating. The patient was initially diagnosed as malaria and hospitalized on Oct. 26, 2014. Microscopic observation revealed typical forms of P. knowlesi in blood smear. The red blood cells became enlarged, with big trophozoites appearing as a ring with dual cores and dark brown malaria pigment. The trophozoites were slightly bigger and thicker than P. falciparum. The schizont had 6-8 merozoites, with obvious brown malaria pigment. PCR resulted in a specific band of 1 099 bp. BLAST analysis showed that the sequence of the PCR product was 99% homologous to P. knowlesi (acession No. AM910985.1, L07560.1 and AY580317.1). The patient was diagnosed as P. knowlesi infection, and was then given an 8-day treatment with chloroquine and primaquine, together with dihydroartemisinin piperaquine phosphate tablet. The patient was discharged after recovery on Oct. 28, 2014. Conclusion: According to the clinical symptoms, epidemiological history and laboratory test, the patient has been confirmed as P. knowlesi infection. It may also be the first active case of knowlesi malaria reported in China.
Asunto(s)
Malaria , Plasmodium knowlesi , Animales , Antimaláricos , Artemisininas , China , Cloroquina , Eritrocitos , Hemoproteínas , Humanos , Microscopía , Reacción en Cadena de la Polimerasa , Primaquina , Quinolinas , TrofozoítosRESUMEN
OBJECTIVE: To analyze the features of malaria epidemic in Guangdong Province in 2011 so as to provide the evidence for the elimination of malaria in Guangdong Province. METHODS: The data from the Disease Reporting Information System of Chinese Center for Disease Control and Prevention were analyzed with the descriptive epidemiological method for the epidemiological characteristics of malaria in Guangdong Province in 2011. RESULTS: A total of 96 malaria cases were reported in Guangdong Province in 2011, with an annual mean incidence of 0.092 per 100 thousand. There were 40 cases of Plasmodium vivax infection, 36 cases of Plasmodium falciparum infection and 20 cases of undivided malaria. There were 2 death cases. There were cases reported in 34 counties/cities/districts of 17 prefecture-level cities in the whole province. The cases distributed mainly in Guangzhou and Shenzhen, where there were 57 cases, reaching 59.38% of the cases of the whole province. There were cases reported every month in the whole year. From May to November, 73 cases were reported, accounting for 76.04% of the cases of the whole year. The ratio of male to female cases was 5.86: 1. The age distribution concentrated mainly on 20-50 years old. The youngest patient was 1 years old and the eldest was 65 years old. The occupation distribution concentrated mainly on the worker, commercial service, peasant, housekeeper and unemployed people (68 cases, 70.83%). In addition to the aforementioned 96 cases of local census register population, there were 32 cases of nonlocal census register population found in Guangdong, 2011. Of the total 128 cases, the main original areas of the imported cases were Africa (77, 60.16%) and Asia (30, 23.44%). The country with the most cases was Nigeria in Africa (36 cases), the second was Angola in Africa (19 cases), and the third was Myanmar in Asia (11 cases). CONCLUSION: The malaria epidemic situation in Guangdong Province is relatively stable in 2011, but the imported cases of Plasmodium falciparum infection increase. Therefore, the surveillance, prevention and control for imported cases of P. falciparum infection should be strengthened.
Asunto(s)
Epidemias/estadística & datos numéricos , Malaria/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Malaria/transmisión , Masculino , Persona de Mediana Edad , Estaciones del Año , Adulto JovenRESUMEN
OBJECTIVE: To understand the endemic situation of schistosomiasis in Guangdong Province. METHODS: The surveillance of Oncomelania hupensis snails and infectious sources was carried out in the former endemic areas, and the surveillance data were statistically analyzed from 2004 to 2009 according to the national and provincial surveillance protocols. RESULTS: From 2004 to 2009, an area of 927.45 hm2 was surveyed and no living snails were found, and 287 out of 12 345 young people living in the endemic areas showed serum positive with the DIGFA, but none of schistosomiasis patients were found. A total of 28 766 mobile population were involved in the DIGFA examination, and 417 persons were positive, among them, 52 chronic patients were found, and 6 patients had eggs in their stools. Through the passive surveillance, 281 cases were reported from 2003 to 2009, and 4 acute cases were reported from 2004 (1 case) to 2005 (3 cases). A total of 9 064 head of cattle were surveyed and none of them was infected with Schistosoma japonicum by stool examination. CONCLUSIONS: The achievements of schistosomiasis control are solidified in Guangdong Province. However, the risk of schistosomiasis transmission still remains. The surveillance should be continued, especially of imported infectious sources and snails.
Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades Endémicas/estadística & datos numéricos , Esquistosomiasis/epidemiología , Esquistosomiasis/veterinaria , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Niño , Preescolar , China/epidemiología , Reservorios de Enfermedades/parasitología , Enfermedades Endémicas/veterinaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Schistosoma/aislamiento & purificación , Schistosoma/fisiología , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Vigilancia de Guardia , Caracoles/parasitología , Adulto JovenRESUMEN
OBJECTIVE: To investigate the natural infection of Angiostrongylus cantonensis in Guangdong Province, and to provide the scientific evidence for control measures. METHODS: The investigation was carried out in 56 villages of 28 towns of 28 counties/districts in East Guangdong, West Guangdong, the mountain area of North Guangdong and Peal River Delta of the Province from 2005 to 2010. The rodents were captured with live trap and the species identified. Angiostrongylus cantonensis adult worms were collected from the hearts and lungs of rodents, examined, counted and the sex of worms identified. RESULTS: The rodents were captured from 2005 to 2010, belonged to 2 orders, 2 families (subfamily), 4 genera and 10 species. Seven species of the rodents were found infected with Angiostrongylus cantonensis in all 28 counties/districts. Totally 5 820 rats were examined and 496 infected ones were identified, with a mean infection rate of 8.52%. The infection rate of rodents was highest in the Peal River Delta, reaching 9.8% (205/2084) (chi2=15.25, P<0.01). Rattus norvegicus had the highest infection rate of 16.9% (310/1 835) (chi2=240.91, P<0.01). The mean intensity of infection was 6.1 worms/rat. 1 125 female and 1064 male worms were found respectively (chi2=1.75, P>0.05). CONCLUSION: Natural infection of Angiostrongylus cantonensis in rodents has been found in all the 56 villages selected from the 4 regions of Guangdong Province.
Asunto(s)
Enfermedades de los Roedores/parasitología , Roedores/parasitología , Infecciones por Strongylida/epidemiología , Angiostrongylus cantonensis , Animales , China/epidemiología , Femenino , Masculino , RatasRESUMEN
Angiostrongyliasis has been frequently reported from the People's Republic of China during the last decade. An outbreak of angiostrongyliasis among migrant laborers in Guangning, Guangdong Province is described here. A questionnaire was developed to collect epidemiological and clinical information about 17 migrant laborers from the Bai ethnic group in Dali, Yunnan Province. Serum samples were collected and tested by enzyme-linked immunosorbent assay. Rats and mollusks from the same area where patients had collected Pomacea canaliculata were examined for presence of Angiostrongylus cantonensis. All 17 Bai migrant laborers consumed P. canaliculata and six had meningitis 3-19 days after consumption of P. canaliculata. Headache, myalgia and fatigue were the most common symptoms. Blood samples from 5 patients were positive for antibodies to A. cantonensis. The places where the migrant laborers collected P. canaliculata were identified as endemic areas for A. cantonensis. This outbreak highlights the vulnerability of migrants to angiostrongyliasis.
Asunto(s)
Angiostrongylus cantonensis/aislamiento & purificación , Enfermedades Transmisibles Emergentes/etnología , Parasitología de Alimentos , Infecciones por Strongylida/etnología , Migrantes , Adulto , Angiostrongylus cantonensis/patogenicidad , Animales , China/epidemiología , Enfermedades Transmisibles Emergentes/sangre , Enfermedades Transmisibles Emergentes/parasitología , Brotes de Enfermedades , Femenino , Humanos , Entrevistas como Asunto , Masculino , Ratas , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/parasitología , Estudios Seroepidemiológicos , Caracoles/parasitología , Infecciones por Strongylida/sangre , Infecciones por Strongylida/parasitología , Adulto JovenRESUMEN
OBJECTIVE: To understand the distribution of Angiostrongylus cantonensis foci in Guangdong Province for making surveillance program. METHODS: Survey sites were chosen by strata sampling according to different geographic locations. Totally 22 survey sites were selected in four regions: East Guangdong, West Guangdong, North Guangdong and the Pearl River Delta. One or two administrative villages in each site were randomly selected for the investigation. Pomacea canaliculata and Achatina fulica collected from fields and other species of freshwater or terrestrial snails obtained in the restaurants and wet markets were examined for the third stage larvae by tissue grinding or lung examination. Rats were captured in the fields, and their hearts and lungs were dissected for adult worms. Rat feces were also collected for the detection of first stage larvae by water precipitation. RESULTS: Large number of P. canaliculata was found in all sites. A. fulica was found in most surveyed sites. Totally 2929 P. canaliculata and 1354 A. fulica were collected with a larva infection rate of 5.9% (172/2929) and 16.5% (223/1354), respectively (P<0.01). The average prevalence among the regions was different (P<0.01) with the highest prevalence in Pearl River Delta (15.6%, 152/975), especially in Dongguan City of the Delta (34.7%, 78/225). 114 Cipangopaludina sp. and 252 Bellamya sp. were bought from wet markets of 9. sites. Larvae were found only in Bellamya snails from Luoding and Kaiping cities with an infection rate of 1.4% (1/70) and 3.3% (3/91), respectively. Totally 491 rats were captured in 9 sites including Rattus norvegicus, R. flavipectus, Suncus murinus, Mus musculus, Bandicota indica, R. losea and R. rattus, with an average infection rate of 11.4% (56/491). Adult worms were found in R. norvegicus, R. flavipectus and B. indica with a prevalence of 19.8% (52/263), 2.5% (3/118) and 10.0% (1/10), respectively. Thirty-four rodent fecal samples were collected in 7 sites and examined with a larva positive rate of 44.1% (15/34). CONCLUSION: Foci of Angiostrongylus cantonensis are widely distributed in Guangdong Province as natural infection has been found in its intermediate and definitive hosts.
Asunto(s)
Angiostrongylus cantonensis/aislamiento & purificación , Interacciones Huésped-Parásitos , Caracoles/parasitología , Infecciones por Strongylida/parasitología , Animales , China/epidemiología , Geografía , Ratas , Infecciones por Strongylida/epidemiologíaRESUMEN
OBJECTIVE: To make a survey on the possible imported cases with microfilaremia from a recently identified outbreak focus in Fuchuan County of Guangxi Region. METHODS: Moving people as temporary laborers from Guangxi and periphery residents were screened by thick blood smears for microfilariae and ELISA for specific IgG4 in Sept 2007. RESULTS: 989 persons in cities/districts of Nansha, Panyu, Shantou and Zhongshan were investigated. Among 150 persons from Changtang administrative village of Guangxi, 47 were from two outbreak focuses, Ganshang and Yinshan natural villages in Changtang. Three cases with microfilaremia were found, with a microfilaraemia density of 24, 20 and 2 per 120 microl blood, respectively. The 3 cases were all from the 2 natural villages, with a microfilaraemia positive rate of 6.4% (3/47). Meanwhile, anti-filaria IgG4 was detected for other 1 501 persons, including those from the outbreak focuses, from surr-founding areas and from non-endemic area as control, fifteen cases were found with IgG4 positive. Of the 15 positive cases, 12 were from the 2 outbreak natural villages, with a positive rate of 25.5%, higher than those of others (chi2=295.83, P < 0.01). The cases with IgG4 positive but microfilaremia negative were reexamined by ICT kit and all showed negative. CONCLUSION: It is suggested that no further transmission occurs although microfilaremia cases have been imported from the outbreak focus of Guangxi.
Asunto(s)
Anticuerpos Antihelmínticos/análisis , Filariasis Linfática/epidemiología , Inmunoglobulina G/análisis , Animales , Anticuerpos Antihelmínticos/sangre , China/epidemiología , Brotes de Enfermedades , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/sangre , Microfilarias/inmunología , Microfilarias/aislamiento & purificaciónRESUMEN
OBJECTIVE: To study the morphology and ecological habits of An. anthropophagus and its role in malaria transmission in Hengqin Island of Zhuhai City, Guangdong Province. METHODS: Mosquitoes were captured through overnight/semi-overnight trapping with human and cattle baits as well as lamp-trapping. The specimens were morphologically identified through describing the adult mosquitoes, eggs and pupae. The relevant parameters were collected to calculate the vectorial capacity of both An. anthropophagus and An. sinensis. RESULTS: There is no morphological difference between the isolate of An. aothropophagus from Hengqin Island and that from Jiangsu Province. Its human blood preference ratio and human blood index was 0.94 and 0.75 respectively, and the vectorial capacity of An. anthropophagus was 7.36 times higher than that of An.sinensis (5.1914/0.7052). CONCLUSION: The isolate of An. anthropophagus from Hengqin Island belongs same species to that from the mainland, which prefers to human blood and shows higher malaria transmission potential.