Adams Vera J, Markus Miles B, Kwitshana Zilungile L, Dhansay Muhammad A, van der Merwe Lize, Walzl Gerhard, Fincham John E
Nutritional Intervention Research Unit, P O Box 19070, Tygerberg 7505, South Africa.
BMC Infect Dis. 2006 May 26;6:88. doi: 10.1186/1471-2334-6-88.
Ascariasis and HIV/AIDS are often co-endemic under conditions of poverty in South Africa; and discordant immune responses to the respective infections could theoretically be affecting the epidemic of HIV/AIDS in various ways. It is well-known that sensitisation to helminthic antigens can aggravate or ameliorate several non-helminthic diseases and impair immunisation against cholera, tetanus and tuberculosis. The human genotype can influence immune responses to Ascaris strongly. With these factors in mind, we have started to document the extent of long-term exposure to Ascaris and other helminths in a community where HIV/AIDS is highly prevalent. In more advanced studies, objectives are to analyse relevant immunological variables (e.g. cytokine activity and immunoglobulin levels). We postulate that when Ascaris is hyperendemic, analysis of possible consequences of co-infection by HIV cannot be based primarily on excretion vs non-excretion of eggs.
Recall of worms seen in faeces was documented in relation to the age of adult volunteers who were either seropositive (n = 170) or seronegative (n = 65) for HIV. Reasons for HIV testing, deworming treatments used or not used, date and place of birth, and duration of residence in Cape Town, were recorded. Confidence intervals were calculated both for group percentages and the inter-group differences, and were used to make statistical comparisons.
In both groups, more than 70% of participants were aware of having passed worms, often both when a child and as an adult. Most of the descriptions fitted Ascaris. Evidence for significantly prolonged exposure to helminthic infection in HIV-positives was supported by more recall of deworming treatment in this group (p < 0.05). Over 90% of the participants had moved to the city from rural areas.
There was a long-term history of ascariasis (and probably other helminthic infections) in both of the groups that were studied. In women in the same community, and in children living where housing and sanitation are better, Ascaris sero-prevalence exceeded egg-prevalence by two- and three-fold, respectively. For ongoing and future analyses of possible consequences of co-infection by Ascaris (and/or other helminths) and HIV/AIDS (and/or other bystander conditions), comparisons must be based mainly on disease-related immunological variables. Especially in adults, comparisons cannot be based only on the presence or absence of eggs in excreta.
在南非贫困环境下，蛔虫病和艾滋病毒/艾滋病往往共同流行；理论上，对这两种感染的免疫反应不一致可能以多种方式影响艾滋病毒/艾滋病的流行。众所周知，对蠕虫抗原的致敏可加重或改善几种非蠕虫疾病，并损害霍乱、破伤风和结核病的免疫接种。人类基因型可强烈影响对蛔虫的免疫反应。考虑到这些因素，我们已开始记录艾滋病毒/艾滋病高度流行社区中长期接触蛔虫和其他蠕虫的程度。在更深入的研究中，目标是分析相关的免疫学变量（如细胞因子活性和免疫球蛋白水平）。我们推测，当蛔虫高度流行时，对艾滋病毒合并感染可能后果的分析不能主要基于虫卵的排泄与否。
记录成年志愿者（艾滋病毒血清阳性者n = 170，血清阴性者n = 65）粪便中所见蠕虫与年龄的关系。记录艾滋病毒检测原因、是否使用驱虫治疗、出生日期和地点以及在开普敦的居住时间。计算组百分比和组间差异的置信区间，并用于进行统计比较。
在两组中，超过70%的参与者意识到自己排出过蠕虫，儿童期和成年期都常有这种情况。大多数描述符合蛔虫。艾滋病毒阳性者对驱虫治疗的回忆更多，这支持了他们长期接触蠕虫感染的证据（p < 0.05）。超过90%的参与者从农村地区搬到了城市。
在所研究的两组人群中都有蛔虫病（可能还有其他蠕虫感染）的长期病史。在同一社区的女性以及居住环境和卫生条件较好地区的儿童中，蛔虫血清阳性率分别比虫卵阳性率高出两倍和三倍。对于正在进行的以及未来对蛔虫（和/或其他蠕虫）与艾滋病毒/艾滋病（和/或其他伴随疾病）合并感染可能后果的分析，比较必须主要基于与疾病相关的免疫学变量。特别是在成年人中，比较不能仅基于排泄物中虫卵的有无。
