Statistics in medicine help provide context and meaning to data collected through research. One must be able to differentiate the quality of the research, decide if there is any bias and if the numbers can back up the research.


COVID-19 spreads via human-to-human transmission through droplets, close contact, or respiratory droplets and is widely accepted based on reports from the World Health Organization (WHO), The Centers for Disease Control and Prevention (CDC) (2020), and other sources of academic research. Kolifarhood et al. (2020) discuss how variables such as overall health, co-morbidities, and the level of viral load one is exposed to can impact the severity of symptoms and incubation period. Kolifoarhood et al. (2020) found the median incubation period for COVID-19 was 5-6 days; however, variances were noted from 2-14 days depending on the location and health history of the patient.

Median Infectivity, Pathogenicity and Incubation

When COVID-19 infectivity was compared to SARS and MERS, it was slightly higher. SARS and MERS infectivity index was 2, meaning each person infected could infect two additional persons. Research conducted for COVID-19 found that the median infection rate was 2.79 persons (Kolifarhood et al., 2020).

Pathogenicity is the “capability of the pathogen to establish and induce infection with different clinical manifestations in humans” (Kolifarhood et al., 2020, p.3). The WHO reported that 82% of infected persons reported mild symptoms, and the median recovery was two weeks, and more severe cases took 3-6 weeks.

Kolifarhood et al. (2020) state that a WHO report found incubation periods ranged between 2-14 days with a median incubation period for human to human transmission as 5-6 days. However, other sources reported incubation periods of 6.4 days up to 24. Differences in findings are partially attributed to the various calculation formulas, and the difference noted for meaningful information is of value as it could form ineffective public health measures.

Helpful Information

Helpful information would include demographics. Including demographics would provide more detailed information regarding what populations are infected or at risk, so public health officials could investigate and provide more focused support to those populations. Additionally, here in Honolulu, we found that the most severe cases in the intensive care unit were due to a delay in care. More research on why people delayed care and how many days on average they waited would be helpful for primary care providers and public service announcements. 


CDC. (2020, March 28). COVID Data Tracker. Centers for Disease Control and Prevention. Retrieved March 21, 2022, from 

 Kolifarhood, G., Aghaali,M., Saadati, H.M., Taherpour, N., Rahimi, S., Izadi, M., & Nazari, S.S.H. (2020, April). . Archives of Academic Emergency Medicine, 8(1): e41.


The incubation period of viral diseases is strongly associated with the clinical characteristics’ patients may present. It marks the disease severity and prognosis - because the time of symptom onset reflects pathogen growth, replication rate, and toxin excretion. The incubation period provides clues about the cause and source of a disease when these factors are unknown (Rogers, n.d.).

As stated by Kolifarhood et al. (2020), some studies performed on individuals who visited Wuhan and Guangdong during the outbreak of COVID-19 revealed a mean of incubation of 4.8 (+ 2.6), 6.4, and 24 days. The range of incubation was 0 to 14 days.

As far as the incubation median, the number of days reported was five to six. The pathogenicity median was two, three, to six weeks, although it only took one week for patients to present more severe symptoms, i.e., hypoxia. The infectivity median was 2.79, with the highest recorded at 6.47 and the lowest at 1.95. Age and underlying health conditions were significant determinant factors of pathogenicity. A case-series study conducted in China determined that infants infected with the virus only experienced mild symptoms and did not require intensive care. On the other hand, individuals over 60 years old were more likely to experience severe disease complications, including death (Kolifarhood et al., 2020).

Information that would be helpful to know and missing includes how COVID-19 has impacted global health and the lessons learned from the virus outbreak. According to Gaspar et al. (2021), the pandemic had an unprecedented impact worldwide, affecting people’s health, the economy, education, and labor (p. 581). One of the most significant lessons learned from the COVID-19 pandemic is the importance of political power and its role in protecting citizens from future pandemics. It appeared that no country was fully prepared to handle a pandemic. Public health systems must remain committed to developing adequate surveillance programs, prompt diagnostic techniques, and robust research initiatives that can detect and understand new organisms' basic biology and treatment (Martínez-Córdoba et al., 2021, p. 3).


Gaspar, T., Paiva, T., & Matos, M. G. (2021). Impact of COVID-19 in global health and psychosocial risks at work. Journal of Occupational & Environmental Medicine, Ahead of Print. 

Kolifarhood, G., Aghaali, M., Mozafar Saadati, H., Taherpour, N., Rahimi, S., Izadi, N., & Hashemi Nazari, S. S. (2020). Epidemiological and clinical aspects of COVID-19: A narrative review. Archives of Academic Emergency Medicine, 8(1), e41-e41. 

Martínez-Córdoba, P.-J., Benito, B., & García-Sánchez, I.-M. (2021). Efficiency in the governance of the COVID-19 pandemic: Political and territorial factors. Globalization and Health, 17(1), 113–113. 

Rogers, K. (n.d.). Why is it important to know the incubation period of a disease? Encyclopedia Britannica. 

Leave a Reply

Your email address will not be published.