(CNN) More babies are dying before their first birthdays in Venezuela as the country is mired a severe economic and political crisis, according to a study published Thursday in The Lancet Global Health.

Venezuela had made significant strides in improving infant survival and had reported steadily decreasing numbers of infant deaths since the 1950s. But the trend began to reverse a decade ago, and in 2016, it had fallen to the infant mortality level last seen in 1999, according to the new study.

Infant mortality in Venezuela reached 21 deaths per 1,000 live births in 2016, according to the study, a rate not seen there since the 1990s. That's well above the average 15 deaths per 1,000 live births in 2017 for Latin America and the Caribbean, including Venezuela, according to the World Bank

The team of researchers estimated mortality for children under 1 year of age using death counts, weekly bulletins and census and survey data. The resulting rates are higher than those reported by the World Health Organization and the UN Economic Commission for Latin America and the Caribbean , whose latest estimates put infant mortality in Venezuela at 15 and 13.8 deaths per 1,000 live births, respectively.

The researchers argue that these organizations have continued to use projections of previous trends in the absence of official government data and says those results don't take into account the recent socioeconomic decline.

The authors of the new study see turmoil in the country as the driver for setbacks in infant survival.

"The increasing infant mortality rate is likely to derive from the progressively deteriorating nutrition status, the collapse in living standards, and a breakdown of the health system," the authors wrote.

The Venezuelan Ministry of Health did not respond to a request for comment.

A crumbling health care system

A 2018 survey of 104 health facilities in Venezuela showed that 79% had no running water; a quarter of pediatric intensive care units, known as ICUs, had closed down; and a vast majority of ICUs reported intermittent failures.

Official statistics have been difficult to come by. In a rare release of information that led to the firing of the health minister in 2017, pregnancy-related deaths were shown to have risen 66% in the two years prior.

As of June 2016, the country faced shortages of more than 80% of the medicines doctors need, according to statistics from the Venezuelan pharmaceutical federation

Vaccinations have also been affected by the shortages, with physician organizations in Venezuela reporting that the government did not provide vaccines against polio, diphtheria, tetanus, pertussis, hepatitis B and Hemophilus influenza type B to children under 5 between 2007 and 2009.

In 2018, the president of the Venezuelan Pediatric Society told a local newspaper that the available vaccinations for children under 5 fell short of covering even 30% of the demand, which left at least 2.9 million children in the country susceptible to illnesses such as diphtheria and measles.

With failed vaccination policies has come a re-emergence of infectious diseases.

The return of infectious diseases

Severe outbreaks of measles, diphtheria and malaria have plagued the country in recent years, according to WHO.

In 2018, there were over 5,000 cases of measles there and 73 deaths from the disease, the highest number reported for all of the Americas.

Malaria, on the other hand, was reported to affect 240,000 people in 2016, an increase of 75% from 2015.

"During important crises, the most common causes of death are the same as those reported in countries with the highest child mortality rates: diarrhoeal diseases, acute respiratory infections, measles, malaria, and severe malnutrition," Jenny Garcia, a researcher at the French Institute for Demographic Studies and author of the new study, said in a news release.

In the face of severe food shortages and widespread poverty, malnutrition has plagued Venezuela for years.

Weight loss and skipped meals have become the norm

Food shortages and inflation have caused a majority of Venezuelans to lose an average of 19 pounds, according to the 2017 National Survey of Living Condition conducted by three major universities in Venezuela. Families substituted meat for cheaper alternatives, reduced portions and ate two or fewer meals per day, which led to a growing number of people who are malnourished and susceptible to illnesses.

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"Poor governance is at the heart of the problem. And it is poor governance that is literally killing the youngest Venezuelans. Much more regional and global pressure must be brought on to bear on the current government to end the denial of the health collapse, rein in hyperinflation, and begin to address the policy failures that are stealing Venezuelans' futures," Chris Beyer, a professor from the Center for Public Health and Human Rights at Johns Hopkins Bloomberg School of Public Health, said in a commentary published alongside the new study in The Lancet Global Health.