Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WC1E 7HT, UK.
Institut de Recherche en Science de La Santé, Bobo-Dioulasso, Burkina Faso.
Malar J. 2022 Mar 9;21(1):77. doi: 10.1186/s12936-022-04098-6.
The populations of moderate or highly malaria endemic areas gradually acquire some immunity to malaria as a result of repeated exposure to the infection. When this exposure is reduced as a result of effective malaria control measures, subjects who benefitted from the intervention may consequently be at increased risk of malaria if the intervention is withdrawn, especially if this is done abruptly, and an effective malaria vector remains. There have been many examples of this occurring in the past, a phenomenon often termed 'rebound malaria', with the incidence of malaria rebounding to the level present before the intervention was introduced. Because the main clinical burden of malaria in areas with a high level of malaria transmission is in young children, malaria control efforts have, in recent decades, focussed on this group, with substantial success being obtained with interventions such as insecticide treated mosquito nets, chemoprevention and, most recently, malaria vaccines. These are interventions whose administration may not be sustained. This has led to concerns that in these circumstances, the overall burden of malaria in children may not be reduced but just delayed, with the main period of risk being in the period shortly after the intervention is no longer given. Although dependent on the same underlying process as classical 'resurgent' malaria, it may be helpful to differentiate the two conditions, describing the later as 'delayed malaria'. In this paper, some of the evidence that delayed malaria occurs is discussed and potential measures for reducing its impact are suggested.
中度或高度疟疾流行地区的人群由于反复接触感染，逐渐对疟疾产生一定的免疫力。当有效的疟疾控制措施减少这种接触时，受益于干预措施的人群如果干预措施被取消，特别是突然取消，并且有效的疟疾传播媒介仍然存在，他们可能会面临更高的疟疾风险。过去已经有许多这样的例子，这种现象通常被称为“反弹疟疾”，疟疾的发病率反弹到干预措施实施之前的水平。由于疟疾在高传播地区的主要临床负担是在幼儿中，因此近几十年来，疟疾控制工作的重点一直放在这一群体上，使用杀虫剂处理过的蚊帐、化学预防以及最近的疟疾疫苗等干预措施取得了巨大成功。这些干预措施的实施可能无法持续。这引起了人们的担忧，即在这种情况下，儿童的疟疾总负担可能不会减轻，而只是被推迟，主要的风险期是在干预措施不再实施后的短时间内。虽然它依赖于与经典的“复燃性”疟疾相同的潜在过程，但将两者区分开来可能会有所帮助，将后者描述为“延迟性疟疾”。本文讨论了一些证据表明延迟性疟疾确实存在，并提出了减少其影响的潜在措施。
