The development of the recent COVID-19 pandemic has affected all segments of the population transversely; however, the infection has been more harmful to some groups of vulnerable subjects, including the homeless and migrants. In these specific populations, the presence of the SARS-CoV-2 virus is not known, and it is possible to imagine them as reservoirs of the virus, hidden sources of contagion and difficult to trace by epidemiological link studies.
Olfactory dysfunction has been reported as a symptom of COVID-19 infection, especially in asymptomatic or paucisymptomatic subjects, in as much as 87% of patients. This suggests special attention to this symptom, as it could be a potential predictor of COVID-19 in otherwise healthy subjects.
Specific studies on prevalence of COVID-19 in fragile populations such as migrants and homeless have never been investigated. Furthermore, data on olfactory dysfunction in COVID-19 patients belonging to these populations are still unknown, as well as their relationship to degree and phase of infection. This research project will include 500 adult migrants and homeless of both sexes that will be reached through the ambulatory service of the Elemosineria Apostolica of the Vatican City State and will 1) perform an epidemiologic analysis of the diffusion of COVID-19 infection in this vulnerable population, relating it to anamnestic and clinical data of the patients, and 2) evaluate the presence of olfactory dysfunction in this population through otolaryngology examination, olfactometry and self-administered questionnaire.
Our results will allow to identify the prevalence and characteristics of COVID-19 in a vulnerable population, and to evaluate the potential role of olfactory dysfunction as an early indicator of infection in these patients, thus allowing to promptly identify affected cases and limit the spread of the infection, especially in fragile populations where it is facilitated by environmental and behavioral conditions.
To date, there are no studies that focused on specific prevalence of COVID-19 in fragile populations such as migrants and homeless in our Country. These subjects are vulnerable groups that are more exposed to contagion and that may act as reservoirs of infection that will further spread infection.
The data that will be collected in this research project about the spread of infection and related health conditions in these fragile populations will allow to obtain important information about the epidemiological and clinical characteristics of infection in these populations, with special attention to asymptomatic or paucisymptomatic patients that had the disease without receiving a diagnosis, and therefore that may potentially contribute to the spread of the infection.
Data from serological tests will indicate if previous Severe Acute Respiratory Syndrome - Coronavirus - 2 (SARS-CoV-2) infection occurred, and therefore that the patient may be protected from a new SARS-CoV-2 infection; if ongoing infection is present, thus activating immediate protocols to limit further contagion; or if no immunoglobulins are present, meaning that the patient is at risk of developing COVID-19 disease. This information, in correlation with clinical data collected in these patients, will allow preventing in the future, and especially in case of a second round of infection, the spread of infection in these types of populations knowing in advance some of the characteristics of infected patients to isolate and treat them.
As per the second objective, the relationship between olfactory dysfunction and COVID-19 infection in a specific fragile population of migrants and homeless has never been investigated. Over the past few months, anosmia or hyposmia have been reported as frequent symptoms of COVID-19 infection, especially in asymptomatic or paucisymptomatic subjects. In these patients, that represent up to four/fifths of cases of COVID-19, the diagnosis of COVID-19 could be missed, because these symptoms were not known to be specific. As a result, the patients are not isolated, and the spread of the virus may continue.
Evidence on the very high prevalence of olfactory dysfunction has accumulated, showing that nearly 90% of COVID-19 patients experience olfactory dysfunction at some point of the infection. Olfactory dysfunction can begin in the few days before infection, during the disease or after other symptoms have recovered. The identification and isolation of these patients is therefore essential to slow down the chain of infection and limit contagion, especially in vulnerable populations where the spread of infection is facilitated by environmental and behavioral conditions. Furthermore, the loss of olfactory function in COVID-19 patients, and especially in those belonging to vulnerable populations, could be an early sign of infection in otherwise healthy patients and could allow to early identify affected cases thus limiting the spread of the infection.
Since the disease is new and the virus is most likely associated with different mutations and clinical patterns, as of yet, there remain more questions than answers. Prevalence of COVID-19 in a vulnerable population composed of migrants and homeless is unknown as it has never been investigated. Furthermore, data on olfactory dysfunction in COVID-19 patients belonging to these populations are still unknown, as well as their relationship to degree and phase of infection.
This research project will allow to perform - for the first time in our Country - an epidemiologic analysis of the diffusion of COVID-19 infection in a fragile population composed of migrants and homeless, relating it to anamnestic and clinical data of the patients. Secondly, it will evaluate the presence of olfactory dysfunction in these subjects to define its burden and evaluate the correlation between olfactory dysfunction and COVID-19 infection in these subjects, with specific attention to degree and phase of infection.
Our results aim at identifying the prevalence and characteristics of COVID-19 in a vulnerable population, and at evaluating the potential role of olfactory dysfunction as an early indicator of infection in these patients, thus allowing to promptly identify affected cases and limit the spread of the infection, especially in fragile populations where it is facilitated by environmental and behavioral conditions.