Background Contact investigation, the systematic evaluation of individuals in close contact with an infectious tuberculosis (TB) patient, is a key active case-finding strategy for global TB control. Better estimates of the yield of contact investigation can guide strategies to reduce the number of underreported and underdiagnosed TB cases, approximately three million cases per year globally. A systematic review (Prospero ID # CRD42019133380) and meta-analysis was conducted to update and enhance the estimates of the yield of TB contact investigation in low- and middle-income countries (LMIC). Pubmed, Web of Science, Embase and the WHO Global Index Medicus were searched for peer-reviewed studies (published between January 2006–April 2019); studies reporting the number of active TB or latent tuberculosis infection (LTBI) found through contact investigation were included. Pooled data were meta-analyzed using a random effects model and risk of bias was assessed. Results Of 1,644 unique citations obtained from database searches, 110 studies met eligibility criteria for descriptive data synthesis and 95 for meta-analysis. The pooled yields of contact investigation activities for different outcomes were: secondary cases of all active TB (defined as those bacteriologically confirmed or clinically diagnosed) 2.87% (2.61–3.14, I2 97.79%), bacteriologically confirmed active TB 2.04% (1.77–2.31, I2 98.06%), and LTBI 43.83% (38.11–49.55, I2 99.36%). Yields are interpreted as the percent of contacts screened who are diagnosed with active TB as a result of TB contact investigation activities. Pooled estimates were substantially heterogenous (I2 ≥ 75%). Conclusions This study provides methodologically rigorous and up-to-date estimates for the yield of TB contact investigation activities in low- and middle-income countries (LMIC). While the data are heterogenous, these findings can inform strategic and programmatic planning for scale up of TB contact investigation activities.

IntroductionAs of July 2022, a little over one-third of Guatemalans were fully vaccinated. While COVID-19 vaccination rates are not officially reported nationally by racial/ethnic groups, non-governmental organisations and reporters have observed that COVID-19 vaccination rates are especially low among high-risk Indigenous populations. We conducted one of the first studies on COVID-19 vaccine acceptance in Indigenous populations in the Central Highlands of Guatemala, which aimed to better understand the barriers to COVID-19 vaccine uptake and how to improve vaccine promotional campaigns.MethodsIn November 2021, we conducted eight focus group discussions (FGDs) with 42 Indigenous men and women and 16 in-depth interviews (IDIs) with community health workers, nurses and physicians in Chimaltenango and Sololá. Using a participatory design approach, our qualitative analysis used constant comparative methods to understand the inductive and deductive themes from the FGD and IDI transcripts.ResultsWe found three major overarching barriers to vaccination within the sampled population: (1) a lack of available easily understandable, linguistically appropriate and culturally sensitive COVID-19 vaccine information; (2) vaccine access and supply issues that prevented people from being vaccinated efficiently and quickly; and (3) widespread misinformation and disinformation that prey on people’s fears of the unknown and mistrust of the medical establishment and government.ConclusionWhen developing COVID-19 vaccine messages, content should be culturally relevant, appropriate for low-literacy populations and in the languages that people prefer to speak. Promotional materials should be in multiple modalities (print, radio and social media) and also have specific Maya cultural references (dress, food and concepts of disease) to ensure messaging connects with intended targets. This study supports the need for more robust research into best practices for communicating about COVID-19 vaccines to marginalised communities globally and suggests that policy makers should invest in targeted local solutions to increase vaccine uptake.

ObjectivesTo evaluate the impact of culturally and linguistically tailored informational videos delivered via social media campaigns on COVID-19 vaccine uptake in Indigenous Maya communities in Guatemala.MethodsOur team designed a series of videos utilising community input and evaluated the impact using a pre–post intervention design. In-person preintervention surveys were collected from a sample of respondents in four rural municipalities in Guatemala in March 2022. Facebook, Instagram and browser ads were flooded with COVID-19 vaccine informational videos in Spanish, Kaqchikel and Kiche for 3 weeks. Postintervention surveys were conducted by telephone among the same participants in April 2022. Logistic regression models were used to estimate the OR of COVID-19 vaccine uptake following exposure to the intervention videos.ResultsPreintervention and postintervention surveys were collected from 1572 participants. The median age was 28 years; 63% (N=998) identified as women, and 36% spoke an Indigenous Mayan language. Twenty-one per cent of participants (N=327) reported watching the intervention content on social media. At baseline, 89% (N=1402) of participants reported having at least one COVID-19 vaccine, compared with 97% (N=1507) in the follow-up. Those who reported watching the videos had 1.78 times the odds (95% CI 1.14 to 2.77) of getting vaccinated after watching the videos compared with those who did not see the videos when adjusted by age, community, sex and language.ConclusionOur findings suggest that culturally and linguistically tailored videos addressing COVID-19 vaccine misinformation deployed over social media can increase vaccinations in a rural, indigenous population in Guatemala, implying that social media content can influence vaccination uptake. Providing accurate, culturally sensitive information in local languages from trusted sources may help increase vaccine uptake in historically marginalised populations.