Cochrane has published a Special Collection of reviews, updated with three reviews, summarizing the evidence on public health measures for infection control and prevention of Covid-19. The topics of the three rapid reviews: “Quarantine” (update, published on September 14th, 2020), “Travel Restrictions” (new, published on September 16th, 2020) and “Broad-based screening” (new, published on September 15th, 2020).

>> The main question of the “Quarantine” rapid review is: Can quarantine measures alone or in combination with other public health measures control the coronavirus disease? According to Cochrane, the lead author of the review, Barbara Nussbaumer-Streit from Danube University Krems, Austria, comments: “We published the first version of this report in April 2020. Since then, we have identified 22 additional studies on quarantine against Covid-19. Although the number of studies has increased significantly in a short period of time, the evidence base is still limited because most studies are mathematical modeling studies that make different assumptions about important model parameters. Evidence suggests that introducing quarantine early in a pandemic and combining quarantine with other public health measures such as: B. physical distancing can help slow the spread of Covid-19. However, it is difficult to assess which combination of measures is best suited to reducing the number of cases and deaths.”
The statements about “travel restrictions” are based on equally uncertain evidence. According to Cochrane, the evidence here is “of very low trustworthiness”, which represents the lowest of four levels of trustworthiness in Cochrane reviews. However, existing modeling studies suggested that cross-border travel restrictions, if implemented early in an outbreak, can lead to a reduction in the number of new cases. Estimates for the size of this effect ranged between 26 and 90 percent and are therefore – as is expressly emphasized – very uncertain. Lead author Jacob Burns from the Ludwig Maximilian University of Munich says: “Travel-related control measures do not take place in a vacuum. Their impact is influenced by other factors, such as the stage of the pandemic, whether community transmission has been detected, or whether other measures such as physical distancing and the wearing of face masks have been implemented. These aspects were rarely examined in the studies included in our review.”
The third review addresses the question of how effective broad-based Covid-19 screening measures actually are. “We are not sure whether combined screening, repeated symptom assessment or rapid laboratory tests make sense,” explains lead author Meera Viswanathan (RTI International, North Carolina, USA). She says: Nevertheless, public health measures such as nose and mouth coverings, physical distancing and quarantine for those who may have been in contact with an infected person remain very important, as “infected people can easily be missed during screening”.
The review she is responsible for shows the uncertainty and differences in the accuracy of screening strategies. The main statements:
• Various screening strategies have been evaluated in observational studies, with people usually only being screened once and not repeatedly. Participants were either asked about symptoms, international travel or exposure to a known or suspected Covid-19 case, or temperature checks or a rapid point-of-care test were carried out.
• Some studies combined screening for symptoms and temperature checks. Each of the screening strategies examined carried a high risk of actually infected people being incorrectly identified as virus-free (false negative results).
• Future population-level screening studies are expected to significantly improve our understanding of the effectiveness and accuracy of screening for Covid-19.
“Special Collection”
In addition, since March 4, 2020, Cochrane has made a continuously updated (last updated on September 2, 2020) collection of all reviews freely accessible in a Covid-19 special collection. This collection is part of a series of Covid-19 collections originally written in English but is now also available in Chinese, Czech, German, Farsi, French, Japanese, Bahasa Malaysia, Polish, Portuguese, Russian and Spanish. This special collection was created by Cochrane in response to the Covid-19 pandemic and aims to provide direct access to systematic reviews most relevant to preventing infections. It also contains reviews relevant to WHO interim guidelines and other potentially relevant reviews from three Cochrane Networks (Cochrane Public Health and Health Systems; Cochrane Musculoskeletal, Oral, Skin and Sensory; and Cochrane Acute and Emergency Care), and also draw on findings from Cochrane groups in the affected regions. Many of the reviews listed in this collection are supplemented by Cochrane Clinical Answers.
However, according to Cochrane, it is important to note that “the reviews included in this collection only summarize the evidence and their inclusion does not automatically mean that the interventions reviewed have been shown to be effective in prevention.” <<