Nyirenda Stanley S, Hang'ombe Bernard M, Kilonzo Bukheti S, Kangwa Henry L, Mulenga Evans, Moonga Ladslav
Central Veterinary Research Institute, P.O. Box 33980, Balmoral, Lusaka, Zambia (
Department of Microbiology and Parasitology, Sokoine University of Agriculture, Box 3019, Morogoro, Tanzania.
J Med Entomol. 2017 May 1;54(3):719-725. doi: 10.1093/jme/tjw220.
A cross-sectional study was conducted in the Eastern part of Zambia that previously reported a plague outbreak. The aim of the study was to evaluate the potential role of pigs, goats, and sheep as sero-surveillance hosts for monitoring plague, and to investigate the flea vectors and potential reservoir hosts to establish the current status of plague endemicity in the district. Serum samples were collected from 96 rodents, 10 shrews, 245 domestic pigs, 232 goats, and 31 sheep, whereas 106 organs were eviscerated from rodents and shrews. As for fleas, 1,064 Echidnophaga larina Jordan & Rothschild, 7 Xenopsylla cheopis (Rothschild), and 382 Echidnophaga gallinacea (Westwood) were collected from these animals in 34 villages. Enzyme-Linked Immunosorbent Assay (ELISA) and Polymerase Chain Reaction (PCR) tests were performed on serum, and organs and fleas to determine IgG antibodies against Fraction 1 antigen and pla gene of Yersinia pestis, respectively. ELISA results showed that 2.83% (95% CI = 0.59-8.05) rodents, 9.0% (95% CI = 5.71-13.28) domestic pigs, 4.7% (95% CI = 2.39-8.33) goats, and 3.2% (95% CI = 0.08-16.70) sheep were positive for IgG antibodies against Fra1 antigen of Y. pestis. On PCR, 8.4% (95% CI = 3.96-15.51) of the rodents were detected with Y. pestis pla gene, whereas all fleas were found negative. The common fleas identified were E. larina from pigs, whereas X. cheopis were the only fleas collected from rodents. The presence of sero-positive animals as well as the occurrence of X. cheopis on local rodents suggests that Y. pestis remains a risk in the district.
在赞比亚东部曾报告过鼠疫疫情的地区开展了一项横断面研究。该研究的目的是评估猪、山羊和绵羊作为监测鼠疫的血清学监测宿主的潜在作用,并调查跳蚤媒介和潜在的储存宿主,以确定该地区鼠疫的流行现状。从96只啮齿动物、10只鼩鼱、245头家猪、232只山羊和31只绵羊身上采集了血清样本,同时从啮齿动物和鼩鼱身上取出106个内脏器官。至于跳蚤,在34个村庄的这些动物身上共采集到1064只拉氏蝠蚤(Echidnophaga larina Jordan & Rothschild)、7只印鼠客蚤(Xenopsylla cheopis (Rothschild))和382只鸡栉首蚤(Echidnophaga gallinacea (Westwood))。对血清、器官和跳蚤进行了酶联免疫吸附测定(ELISA)和聚合酶链反应(PCR)检测,分别以确定针对鼠疫耶尔森菌1号抗原的IgG抗体和鼠疫耶尔森菌的pla基因。ELISA结果显示,2.83%(95%置信区间=0.59 - 8.05)的啮齿动物、9.0%(95%置信区间=5.71 - 13.28)的家猪、4.7%(95%置信区间=2.39 - 8.33)的山羊和3.2%(95%置信区间=0.08 - 16.70)的绵羊针对鼠疫耶尔森菌Fra1抗原的IgG抗体呈阳性。PCR检测发现,8.4%(95%置信区间=3.96 - 15.51)的啮齿动物携带鼠疫耶尔森菌pla基因,而所有跳蚤检测均为阴性。鉴定出的常见跳蚤是来自猪的拉氏蝠蚤,而印鼠客蚤是从啮齿动物身上采集到的唯一跳蚤。血清学阳性动物的存在以及当地啮齿动物身上出现印鼠客蚤表明,鼠疫耶尔森菌在该地区仍然构成风险。