Guizhou province, situated in southwest China, has a high incidence of TB and SF. The COVID-19 pandemic swept the world in 2020, prompting Guizhou to implement a series of prevention and control measures. Among these, the most critical measure mandated wearing masks in public places, such as buses, subways, hospitals, cinemas, and shopping malls22,23. People were also advised to limit participation in crowded activities during the worst of the pandemic, and public gathering places were disinfected more frequently than before24,25. The primary purpose of these actions was to reduce the likelihood of COVID-19 patients releasing pathogens into the air and healthy individuals inhaling them. These prevention and control measures were in place in Guizhou province until September 2021, with no new local COVID-19 patients reported26,27. This study aims to explore the impact of long-term COVID-19 prevention and control on other respiratory infectious diseases, selecting TB and SF as representatives of chronic and acute respiratory infectious diseases, respectively.
The study utilized the exponential smoothing model to predict the number of TB and SF cases in Guizhou Province, with the parameters and test results of the prediction model demonstrating its success. The research revealed that COVID-19 prevention and control measures also positively impacted TB and SF, suggesting similar effects on other respiratory infectious diseases. The most useful measure was wearing a mask28,29, and the study's results indicated varying impacts on acute and chronic respiratory infectious diseases. Some research has demonstrated that the COVID-19 pandemic affected the number of infectious disease cases based on their mode of transmission30,31. However, these studies only showed a decline in some infectious diseases due to the pandemic, rather than using predictive models to explore the causes, such as the duration and intensity of the impact on different infectious diseases.
A rapid decline in both TB and SF cases occurred in the first 1–2 months under COVID-19 prevention and control measures. At that time, the focus was primarily on COVID-19, with active detection of other infectious diseases, such as TB and SF, being reduced or temporarily halted. Furthermore, patients' willingness and behavior in seeking medical care were affected. Additionally, the COVID-19 prevention and control measures reduced the spread of SF, an acute respiratory infectious disease with an incubation period as short as 1–7 days32,33. This led to a short-term decrease in SF cases.
Moreover, the research results showed that the long-term decrease in the number of SF cases did not persist in the context of COVID-19 prevention and control measures, returning to the predicted state about 7 months later. This was likely due to the public's declining willingness to comply with regular prevention and control measures and increasing psychological fatigue34. In contrast, apart from the initial 1–2 month decline, TB began to decline significantly after the 11th month, with the downward trend lasting 7 months or even longer. As TB is a chronic respiratory infectious disease with a long incubation period (from 6 months to over a year or more)35,36, COVID-19 prevention and control measures reduced the spread of Mycobacterium tuberculosis and infection possibilities in healthy people. However, the effect could only be observed after several months, becoming particularly evident in areas with severe TB epidemics, such as Guizhou province.
The study revealed that the normalized COVID-19 prevention and control measures in Guizhou province might have a long-term impact on TB, potentially maintaining a decline in the number of TB cases for 7 months or even longer after 11 months of implementation. In contrast, the impact of these measures on SF may be short-term, with cases declining for approximately 6 months. It is also believed that limited contact between people due to lockdowns, working from home, and stay-at-home strategies played a crucial role in decreasing exposure to pathogens related to diseases such as TB and SF.
Spatial aggregation analysis demonstrated that the normalized COVID-19 prevention and control measures effectively reduced TB and SF cases. In 88 counties in Guizhou, TB and SF cases exhibited reductions to varying degrees, particularly in areas with the highest number of cases. However, these areas remain the most severely affected.