Demanou Maurice, Pouillot Régis, Grandadam Marc, Boisier Pascal, Kamgang Basile, Hervé Jean Pierre, Rogier Christophe, Rousset Dominique, Paupy Christophe
Virology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon.
Epidemiology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon.
PLoS Negl Trop Dis. 2014 Jul 10;8(7):e2950. doi: 10.1371/journal.pntd.0002950. eCollection 2014 Jul.
Dengue is not well documented in Africa. In Cameroon, data are scarce, but dengue infection has been confirmed in humans. We conducted a study to document risk factors associated with anti-dengue virus Immunoglobulin G seropositivity in humans in three major towns in Cameroon.
METHODOLOGY/PRINCIPAL FINDINGS: A cross sectional survey was conducted in Douala, Garoua and Yaounde, using a random cluster sampling design. Participants underwent a standardized interview and were blood sampled. Environmental and housing characteristics were recorded. Randomized houses were prospected to record all water containers, and immature stages of Aedes mosquitoes were collected. Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects. Anti-dengue IgG were found from 61.4% of sera in Douala (n = 699), 24.2% in Garoua (n = 728) and 9.8% in Yaounde (n = 603). IgM were found from 0.3% of Douala samples, 0.1% of Garoua samples and 0.0% of Yaounde samples. Seroneutralization on randomly selected IgG positive sera showed that 72% (n = 100) in Douala, 80% (n = 94) in Garoua and 77% (n = 66) in Yaounde had antibodies specific for dengue virus serotype 2 (DENV-2). Age, temporary house walls materials, having water-storage containers, old tires or toilets in the yard, having no TV, having no air conditioning and having travelled at least once outside the city were independently associated with anti-dengue IgG positivity in Douala. Age, having uncovered water containers, having no TV, not being born in Garoua and not breeding pigs were significant risk factors in Garoua. Recent history of malaria, having banana trees and stagnant water in the yard were independent risk factors in Yaounde.
CONCLUSION/SIGNIFICANCE: In this survey, most identified risk factors of dengue were related to housing conditions. Poverty and underdevelopment are central to the dengue epidemiology in Cameroon.
登革热在非洲的记录并不完善。在喀麦隆，相关数据匮乏，但已在人类中确诊有登革热感染。我们开展了一项研究，以记录喀麦隆三个主要城镇中与人类抗登革病毒免疫球蛋白G血清阳性相关的危险因素。
方法/主要发现：采用随机整群抽样设计，在杜阿拉、加鲁阿和雅温得进行了横断面调查。参与者接受了标准化访谈并采集了血液样本。记录了环境和住房特征。对随机抽取的房屋进行勘查，记录所有储水容器，并收集伊蚊的幼虫阶段。对血清进行抗登革病毒IgG和IgM抗体筛查。使用具有随机效应的逻辑回归方法测试血清阳性的危险因素。在杜阿拉，61.4%的血清（n = 699）检测出抗登革IgG，在加鲁阿为24.2%（n = 728），在雅温得为9.8%（n = 603）。在杜阿拉样本中，0.3%检测出IgM，在加鲁阿样本中为0.1%，在雅温得样本中为0.0%。对随机选择的IgG阳性血清进行血清中和试验表明，杜阿拉72%（n = 100）、加鲁阿80%（n = 94）和雅温得77%（n = 66）的血清具有针对登革病毒2型（DENV - 2）的特异性抗体。在杜阿拉，年龄、临时房屋墙壁材料、院子里有储水容器、旧轮胎或厕所、没有电视、没有空调以及至少出城旅行过一次与抗登革IgG阳性独立相关。在加鲁阿，年龄、有未加盖的储水容器、没有电视、不是在加鲁阿出生以及不养猪是显著的危险因素。近期疟疾史、院子里有香蕉树和积水是雅温得的独立危险因素。
结论/意义：在本次调查中，大多数确定的登革热危险因素与住房条件有关。贫困和不发达是喀麦隆登革热流行病学的核心因素。
