Image credits: Tomas Martinez
News Article

COVID-19 Update, Where is the Third Wave?

By Rodrigo Brugada | Mon, 05/10/2021 - 12:49

After Mexico faced two deadly COVID-19 “waves,” when cases and deaths spiked, experts warned of that a third one would follow spring break. The third wave has not materialized and experts are pondering why.


The first deadly wave took place between July and September 2020 and the second between December 2020 and February 2021. Before spring break, many experts and government officials warned about a third wave expected to hit by mid-April. Yet, despite the expectations at the time, official cases decreased. The trend continued and now Mexico reports an average of about 13 new infections per 100,000 people, representing a downward trend in infections of about 14 percent, according to Reuters.


There are many possible explanations as to why this could be happening. One explanation is that there could be enough immunity to provide society-wide protection, akin to herd immunity. So far, Mexico has applied at least one dose of a COVID-19 vaccine to about 10 percent of its population and around 7 percent have been fully vaccinated, according to Our World in Data. Those vaccinated make up an important proportion of people with immunity. Another significant share of the immunity pool comes from those who contracted COVID-19 in the past and may have developed lasting immunity. This immunity may protect up to 8 months after recovery, as stated by the NIH. This is particularly relevant given that almost 1.9 million people have contracted the disease and recovered. Besides, estimates made by IMSS indicate that around 42 percent of the population has generated antibodies.


Another possible explanation comes in the form of testing and reporting. According to Worldometers, as of May 2021, Mexico ranks #162 worldwide in testing per million inhabitants. The country’s positivity rate remains around 18 percent, following a downward trend since January, pointing to a significant potential for underdiagnosis and uncontrolled transmission. According to a case study by UCSF’s Institute of Global Health Sciences, limited testing has been a hurdle for implementing infection control measures, including isolation of positive cases and contact tracing. These types of proactive testing lie at the core of infection control. Mexico City was one of the only states to implement a modest contact tracing strategy in June 2020, with a digital platform, but it has yielded limited results.


The most apparent explanation, and the one the government seems to be adopting, is that the implemented measures kept spread under control, as stated by Health Subsecretary Hugo López-Gatell. This led the government of Mexico City to relax measures and change the COVID-19 traffic light, which is now in yellow. This relaxation of measures entails, among other measures, that shops, cinemas and restaurants will be able to operate at a 40 percent capacity, outdoor sports can be held at a 25 percent capacity and theaters can return to in-person performance at a 30 percent capacity. While this may be an essential step towards economic recovery, it should be noted that the pandemic is still not under control. Official records show that Mexico City has only vaccinated 2.6 million inhabitants, and around 1.6 million of those are still waiting for a second dose. Besides, the world has yet to see the effect the new variants may have on transmission rates. 


Despite the ease in measures, a third wave might still be lurking in the distance.


The data used in this article was sourced from:  
Reuters, Our World in Data, NIH, Microorganisms, Worldometers, UCSF Institute of Global Health Sciences, El Universal, Mexico City Government
Photo by:   Tomas Martinez, Unsplash
Rodrigo Brugada Rodrigo Brugada Journalist & Industry Analyst