Grabowsky Mark, Nobiya Theresa, Selanikio Joel
American Red Cross, USA.
Trop Med Int Health. 2007 Jul;12(7):815-22. doi: 10.1111/j.1365-3156.2007.01862.x.
Mass, free distribution (Catch-up) of insecticide-treated bednets (ITNs) during measles vaccination campaigns achieves immediate, high and equitable coverage for both ITNs and measles vaccine. Maintaining high coverage over time requires long-term, routine access to new nets (Keep-up). In many settings, only one approach--either campaign or routine delivery--has been available and have been seen as competing methods. Relying only on campaigns achieves high coverage at the cost of lack of later access. Relying solely on routine coverage builds a delivery infrastructure but may lead to slower rates of coverage and inequities. A combined Catch-up/Keep-up approach has been a common feature of vaccination programs for many years. We assessed the 3-year effects of a one-time Catch-up campaign followed by clinic-based social marketing for routine Keep-up on ITN coverage and use.
In December 2002, ITNs were distributed to all children attending a measles vaccination campaign in a rural district of Ghana. In the 3 years following that campaign, the district began offering ITNs at a subsidized price to pregnant women attending ante-natal clinics. This Keep-up scheme did not become fully operational until 2 years after the campaign. A coverage survey was conducted 38-month post-campaign using a standard two-stage cluster sampling method.
Coverage of nets was high due to the combined contributions of both Catch-up and Keep-up. There were 475 households in the survey with at least one child less than 5 years of age. Among these households, coverage was 95.6% with any net, 83.8% with a campaign net, and 73.9% with an ITN. Of all children, 95.7% slept in a household that had a net, 86.1% slept in a household that had a campaign net. Not all available nets were used as only 59.6% of children slept under an ITN. The source of the nets was 77.7% from the campaign and 20% from routine clinics. Compared to households that participated in the campaign, households with children born after the campaign had higher rates of net ownership (75.1% vs. 67.7%, P=0.04). Equity was high as the ratio of coverage in the lowest wealth quintile to that in the highest was 0.95 for ITN ownership and 1.08 for ITN use. These coverage and use rates were similar to those previously reported 5-month post-campaign, suggesting no decrease over 3 years.
A high level of ITN coverage and use was achieved and sustained by sequential community-based mass campaign Catch-up and clinic-based Keep-up distribution. The campaign nets covered virtually all extant households while clinic-based distribution provided nets for the new sleeping spaces created post-campaign. Because nets can be shared, and most children are born into families that already have a net, the number of new nets needed to sustain high coverage is substantially lower than the number of newborn children. A Catch-up/Keep-up strategy combining mass campaigns for children and clinic-based distribution to pregnant women is an efficient strategy for achieving and sustaining high net coverage. Assuring proper use of nets is a remaining challenge.
在麻疹疫苗接种活动期间大规模、免费分发（补充）经杀虫剂处理的蚊帐（ITN），可使ITN和麻疹疫苗立即实现高覆盖率且覆盖范围公平。随着时间推移维持高覆盖率需要长期、常规地获取新蚊帐（持续供应）。在许多情况下，只有一种方法——要么是活动分发，要么是常规发放——可用，且这两种方法被视为相互竞争的方式。仅依靠活动分发可实现高覆盖率，但代价是后续无法获取蚊帐。仅依靠常规覆盖可建立分发基础设施，但可能导致覆盖率提升速度较慢且存在不公平现象。多年来，补充/持续供应相结合的方法一直是疫苗接种计划的一个共同特点。我们评估了一次性补充活动后，通过基于诊所的社会营销进行常规持续供应对ITN覆盖率和使用情况的3年影响。
2002年12月，在加纳一个农村地区，向所有参加麻疹疫苗接种活动的儿童分发了ITN。在该活动后的3年里，该地区开始以补贴价格向在产前诊所就诊的孕妇提供ITN。这种持续供应计划直到活动后2年才全面实施。活动后38个月，采用标准的两阶段整群抽样方法进行了覆盖率调查。
由于补充和持续供应的共同作用，蚊帐覆盖率很高。调查中有475户家庭至少有一名5岁以下儿童。在这些家庭中，任何蚊帐的覆盖率为95.6%，活动分发的蚊帐覆盖率为83.8%，ITN的覆盖率为73.9%。在所有儿童中，95.7%睡在有蚊帐的家庭中，86.1%睡在有活动分发蚊帐的家庭中。并非所有可用蚊帐都被使用，只有59.6%的儿童睡在ITN下。蚊帐的来源77.7%来自活动分发，20%来自常规诊所。与参加活动的家庭相比，活动后出生儿童的家庭蚊帐拥有率更高（75.1%对67.7%，P = 0.04）。公平性很高，因为最贫困五分之一人口的ITN拥有率与最富裕五分之一人口的ITN拥有率之比为0.95，ITN使用率之比为1.08。这些覆盖率和使用率与活动后5个月报告的相似，表明3年内没有下降。
通过基于社区的大规模补充活动和基于诊所的持续供应分发，实现并维持了较高水平的ITN覆盖率和使用率。活动分发的蚊帐几乎覆盖了所有现有家庭，而基于诊所的分发为活动后新增的睡眠空间提供了蚊帐。由于蚊帐可以共享，且大多数儿童出生在已经有蚊帐的家庭中，维持高覆盖率所需的新蚊帐数量大大低于新生儿数量。将针对儿童的大规模活动与针对孕妇的基于诊所的分发相结合的补充/持续供应策略是实现并维持高蚊帐覆盖率的有效策略。确保正确使用蚊帐仍是一项挑战。
