Infection Prevention Hot Topic: Vaccines Prevent COVID-19 Reinfection

One of the big questions we have had since the launch of an effective vaccine is whether it can protect us from infections and illnesses. They are effective against severe illness and hospitalization, but what about asymptomatic infections? Answering this ongoing question is not easy, but it is the question we are facing more and more.

A New research Was announced in Weekly morbidity and mortality reports (MMWR) evaluated both Pfizer and Modana vaccines for SARS-CoV-2 infection in healthcare workers, first responders, and key workers.

This longitudinal cohort of HERS-RECOVER studies summarizes not only symptoms, but also individuals vaccinated with “self-collected weekly ENT swabs, regardless of COVID-19-related illness.” It straddled eight locations in the United States that monitored the disease. At the onset of COVID-19-related illness, the condition of the symptoms was confirmed and additional nasal swabs and saliva samples were collected. Investigators said, “Of the 5077 participants, those who have a SARS-CoV-2 infection test record prior to enrollment starting in July 2020 (608), or a longitudinal section until the first day of vaccination. Those identified as part of a targeted surveillance (240) were excluded. Another 279 were excluded due to low participation (ie, they were unable to complete more than 20% of the study week’s surveillance and were unable to complete the surveillance. Did not contribute to specimens of COVID-19-related illnesses). Overall, 3950 participants in the vaccine efficacy analysis sample were analyzed. “

Participants included doctors, nurses and healthcare professionals, 62% of whom were women. Seventy-five percent of participants received at least one dose during the study period, and overall, 5.2% were diagnosed with SARS-CoV-2 infection via RT-PCR.

“During 116,657 man-days when participants were not vaccinated, 161 PCR-confirmed infections were confirmed (incidence = 1.38 / 1,000 man-days). Immunity was considered uncertain. Thirteen days (67,483 man-days) after the first or second vaccination, 33 PCR-confirmed infections were identified and excluded from the results. Partially vaccinated day. Two sources have been reported. “

After a 13-week survey of these frontline responders at eight locations, these 3950 participants helped gain important insights into protection from infection. Under these real-life conditions, fully vaccinated individuals have 90% protection against infection, regardless of symptoms, and even partial vaccination provides 80% protection against infection. I did. More research is needed, but this is a very promising beginning.

CDC SARS-CoV-2 Fomite Transmission Update

This week, the US Centers for Disease Control and Prevention (CDC) released new scientific updates on surface propagation and indoor community environments. The topics “Overcleaning” and “Hygiene Theater” have been used extensively in recent months as they have been found to be susceptible to fomite infections but generally at low risk. From an infection prevention and epidemiologist’s point of view, it is important to note that when dealing with new respiratory pathogens, treat them the same as with previous ones. Transmission of vectors in influenza and RSV is possible, more common, and was a concern during previous outbreaks of the coronavirus.

The focus on sanitary theaters and over-cleaning became an issue as people bleached groceries and quarantined mail, but now how to communicate this is a bigger concern. I will. It is still important to clean, disinfect and use hand hygiene. The CDC reiterates that “people can become infected with SARS-CoV-2 through surface contact.” However, based on available epidemiological data and studies of environmental transmission factors, surface transmission is not considered to be the major pathway for SARS-CoV-2 to spread and the risk is low.The main modes in which people are infected with SARS-CoV-2 are Exposure to respiratory droplets carrying infectious virus.. We recommend cleaning and disinfecting the infected person within 24 hours of witnessing the indoor community. The CDC also reiterated that source control (masking) is an excellent way to avoid contamination, as well as hand hygiene and other efforts to avoid bioburden.