COVID-19 Update: Can we predict today the spread of transmission?

New findings from different researchers seem to indicate that significant community transmission of COVID-19 were produced in areas with an average temperatures of 5-11ºC, combined with low humidity. We need to follow next weeks evolution in Latino American regions to confirm or modify that prediction.


The impact of a COVID-19 outbreak in Latin America and the Caribbean could be considerable, with the possibility of the health services being overwhelmed by massive demands for hospital care, particularly specialist services and intensive care.

The region has both strengths and weaknesses when it comes to dealing with the spread of the virus.

Prominent among the strengths are the time and lessons acquired over the last three months. Drastic decisions have been taken earlier from most governments and strict control measures put in place. The demographic structure also helps, with predominantly youthful populations, something that in principle should tend to reduce the number of acute cases.


PAHO has recommended that countries intensify their COVID-19 preparation and response plans in anticipation of new cases appearing, and said that, ‘for several weeks, countries in the Americas have been preparing for the possible importation of cases of COVID-19. A strong emphasis on stopping transmission continues to be an important objective while recognising that the situation may vary from country to country and will require tailored responses’.

The key to tackling COVID-19 is not to focus on preventing its inevitable arrival but rather to appropriately restrict its spread. An adequate response involves having enough resources available: strengthening surveillance, training the health services, the prevention of propagation and the maintenance of essential services to slow down the transmission and save lives.

The region faces the pandemic with several deficiencies, however, particularly shortcomings in health infrastructure and financing capacities. The most serious problem is that many of the health systems in the region lack the infrastructure and resources needed to tackle the rapid spread of the new virus. All its health systems aspire to universal coverage, but in practice most offer only partial coverage, as a 2019 report from the London School of Economics makes clear. Only Costa Rica and Uruguay meet the WHO recommendation that medium and medium-high income countries invest 6% of their GDP on healthcare.


Owing to the characteristics of the disease, which has a low mortality rate but is highly contagious, appropriate venues are required not only for treating patients but also for isolating them. In many countries there are acute shortages of isolation quarters in terms of isolation rooms for infections transmitted by air and the hospital infrastructure.


A previous results pre-published from Sajadi et al. to examine the influence of environmental factors on COVID-19 and to determine whether climate could be a factor in the spread in this desease show a significant community spread in cities and regions along the 30-50º N' corridor at consistently similar weather patterns with average temperatures of 5-11ºC, combined with low specific (3-6 g/kg) and absolute humidity (4-7 g/m3). The distribution of significant community outbreaks along restricted latitude, temperature, and humidity are consistent with the behavior of a seasonal respiratory virus.


Using weather modeling, it may be possible to predict the regions most likely to be at higher risk of significant community spread of COVID-19 in the upcoming weeks, allowing for concentration of public health efforts on surveillance and containment.

Such models would allow to explore questions such as what are Latino American regions most at risk and for how long and, therefore, where to intensify large scale surveillance and tighten control measures to prevent spreading.


Finally, the Coronavirus Pandemic should be reminder of how vital water is to our lives. Here you can download two interesting reports on water, sanitation, hygiene and wastewater treatment:


AEAS Report. COVID-19. Agua y Saneamiento.

WHO Technical Brief. Water, Sanitation, Hygiene and waste management for COVID-19.