Health experts fear Brazil’s Covid-19 catastrophe could get even worse in the coming months, while a parliamentary inquiry into the government’s response to the pandemic is expected to ratchet up political pressure on President Jair Bolsonaro.

South America’s largest country, previously renowned for demonstrating leadership during health crises, has become an international pariah amid the coronavirus pandemic. Brazil has recorded the highest coronavirus-related death toll in the world outside the U.S., is lagging in terms of vaccinations and is still without an effective and coordinated public health response to the outbreak.

An official inquiry, approved by Brazil’s Supreme Court, was opened late last month to investigate the government’s handling of the pandemic that has killed more than 430,000 people. The inquiry could pave the way to Bolsonaro’s impeachment, though analysts say political opponents of the right-wing leader may prefer to contest the president at elections in October 2022.

Bolsonaro has reportedly said he is “not worried” about the inquiry. A spokesperson for Brazil’s government did not respond to a request for comment when contacted by CNBC.

Bolsonaro has repeatedly spoken out against public health measures, which have become a political battlefield in Brazil, and continues to oppose any lockdown measures to curb the spread of the virus.

“The current unmitigated epidemic won’t be overcome without a dramatic change of direction,” said Dr. Antonio Flores, an infectious disease specialist and Covid medical advisor for aid group Medecins Sans Frontieres in Brazil.

He said that if life continues as normal “at such high daily incidence, one can only expect a new wave of cases, additional thousands of deaths and more pressure on the already stretched health system.”

His comments echo warnings from other health experts that say Brazil could soon see a third wave of Covid infections in the coming weeks. It is feared that the country’s lackluster vaccination effort won’t be enough to prevent a new surge during the winter months of June through to September, with indoor gatherings and activities especially risky.

Flores told CNBC that all available public health measures should be stepped up “as soon as possible” and the country’s vaccination campaign needs to be accelerated. He added that an effective testing and tracing system along with coherent guidance on public health restrictions must also be implemented.

As of May 12, around 15% of Brazil’s population of roughly 211 million have received at least one dose of a Covid vaccine, according to statistics compiled by Our World in Data. Chile, meanwhile, has vaccinated close to 46% of its population with at least one dose of a Covid vaccine, reflecting one of the highest vaccination rates worldwide.

Brazil’s lower rate of vaccination means millions of people nationwide, and beyond its borders, are at risk from more than 90 variants of the coronavirus currently circulating in the country — in addition to any new mutations that may emerge.

Brazil’s Covid vaccination campaign is in stark contrast to its response to the H1N1 swine flu pandemic in 2009, when it vaccinated 92 million people against the virus in just three months. The key difference this time around, analysts say, is Bolsonaro’s refusal to embrace a science-led approach to the health crisis.