Every year, about 2.7 million Americans visit the Dominican Republic. For the vast majority of them, their vacations are uneventful.
The U.S. State Department has confirmed it is investigating the deaths of at least six American tourists in the Dominican Republic since the summer of 2018. Some of them died in what appeared to be bizarre — and similar — circumstances. The agencies are not yet releasing further details about the investigations.
“It’s definitely very strange,” Reynold A. Panettieri Jr., a physician at Rutgers who specializes in toxicology and is not directly involved in the investigations, tells PEOPLE. “Healthy people don’t just die. And the couple dying at the same time certainly tips us off that something is very wrong.”
Panettieri tells PEOPLE that the investigation into the deaths will need to be thorough — and that there are many possible things to check.
Several people fell ill after taking a drink from their hotel minibar, leading some to believe that tainted alcohol could be the culprit. “It is possible for drinks from the minibar to contain a toxin,” speculates Panettieri, “so if that’s the common denominator, that’s always a possibility.”
Other people, including a Colorado couple who fell ill, believe that they were sickened by pesticides — a situation that Panettieri says wouldn’t be surprising.
“Americans don’t like bugs,” he says, “so a lot of tourist destinations treat with pesticides. But outside the U.S., there are less regulations on a lot of pesticides, which means that they can make people sick. It has happened before.”
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Currently, the CDC and the FBI are investigating four deaths at various Grand Bahia Principe properties: Nathaniel Edward Holmes, 63, and Cynthia Ann Day, 49, were found dead in their hotel room May 30 at the Bahia Principle La Romana. Five days earlier, Miranda Schaup-Werner, 41, collapsed shortly after mixing a drink from the minibar in the Luxury Bahia Principe Bouganville in La Romana. Last year, Pennsylvania native Yvette Monique Sport, 51, collapsed at the Bahia Príncipe resort in Punta Cana.
Additionally, authorities are investigating the deaths of two Americans at the Hard Rock Hotel & Casino in Punta Cana. David Harrison, 45, died in July 2018. Robert Bell Wallace, 67, died last April.
“This will be a long investigation,” Panettieri tells PEOPLE. “But they’ll figure it out.”