Carabaña Morales Julio
Departamento de Sociología Aplicada. Facultad de Educación. Universidad Complutense de Madrid. Madrid. España.
Rev Esp Salud Publica. 2020 Nov 17;94:e202011159.
This research (EP-Covid19-Madrid) was inspired on the lack in the middle of March 2020 of data on COVID-19 produced from representative samples. Its goal was to evaluate the potential of interviewing such type of samples in order to assess the incidence and prevalence of epidemics as COVID-19.
The sample was of 211 households in the city of Madrid, with one informant for all household members (571). Households were selected through random generation of phone numbers, informants through sex and age quotes. A questionnaire was applied on April/3/20, with a list of symptoms and basic socio-demographic questions for the informant and a general question on COVID-19 for co-residents. Data was analyzed through cross-tabulations and logistic regression.
Prevalence for individuals. On April/3/20, 10,9% of people 18 years and older living in Madrid reported symptoms compatible with COVID19 (SCC19). Occurrence of SCC19 was similar for both sexes, being respectively above and below the mean for the 40-49 (18,9%) and for the >69 (4%) age groups, showing no relation with household size, but being associated with economic activity (19% among working population) and, even more strongly, with the fact of living with symptomatic co-residents (52%). As for households, there was one member with SCC19 in 17% of households. In 8% of the households two or more members presented SSC19, in fact representing 42,9% of the people in these multiply affected households.
Prevalence of SSC19 was much higher than officially reported for COVID-19, although surprisingly low for people of >65. This prevalence associates with work and intra-home transmission. The inter and intra-home prevalence rates (17% and 42,9% respectively) might be useful to assess the proportion of asymptomatic carriers. These results would benefit from confirmation in larger surveys, preferably also including COVID-19 serological testing.
本研究（EP-Covid19-马德里）的灵感来源于2020年3月中旬缺乏来自代表性样本的新冠病毒数据。其目的是评估对这类样本进行访谈以评估新冠疫情发病率和流行率的潜力。
样本来自马德里市的211个家庭，每个家庭有一名信息提供者（共571人）。家庭通过随机生成电话号码选取，信息提供者根据性别和年龄配额选取。于2020年4月3日发放问卷，其中包括一份针对信息提供者的症状清单和基本社会人口统计学问题，以及一个针对同住居民的关于新冠病毒的一般性问题。数据通过交叉表和逻辑回归进行分析。
个体患病率。在2020年4月3日，居住在马德里的18岁及以上人群中，10.9%报告有与新冠病毒相符的症状（SCC19）。SCC19在两性中的发生率相似，在40-49岁年龄组（18.9%）高于平均水平，在69岁以上年龄组（4%）低于平均水平，与家庭规模无关，但与经济活动相关（在职人口中为19%），甚至更强烈地与有症状同住居民的情况相关（52%）。至于家庭，17%的家庭中有一名成员患有SCC19。8%的家庭中有两名或更多成员出现SSC19，实际上占这些多重感染家庭中人口的42.9%。
SSC19的患病率远高于官方报告的新冠病毒患病率，尽管令人惊讶的是65岁以上人群的患病率较低。这种患病率与工作和家庭内传播有关。家庭间和家庭内的患病率（分别为17%和42.9%）可能有助于评估无症状携带者的比例。这些结果将受益于在更大规模调查中的确认，最好还包括新冠病毒血清学检测。
