Public health has been top of mind for many the last couple of years, but a public health problem has largely flown under the radar: a growing rate of sexually transmitted diseases and infections.

The number of STD and STI cases among Americans has been rising steadily each year since 2014. Even the pandemic, which trapped millions inside their homes, didn't make a dent in those numbers, and it might have worsened.

These rising numbers have led many health officials to raise an alarm and urge action. Many experts believe one of the causes behind this problem is the lack of knowledge about the basic principles of safe sex, typically taught in sex education classes.

In fact, a Centers for Disease Control survey from 2019 showed that nearly 46% of sexually active high school students did not use a condom the last time they had sex. That's a huge problem considering the fact that out of all new STDs reported to the CDC each year, half were among young people aged 15 to 24.

The numbers show there were 2.4 million cases of chlamydia, gonorrhea and syphilis in 2020, which is the most recent year of data.

Chlamydia is currently the most common STD in the U.S., with 1.6 million cases reported to the CDC that year. While its numbers saw a slight drop from 2016, the CDC notes that the drops are probably not really because of an actual drop in infections. Since chlamydia is usually asymptomatic, case rates are heavily influenced by screening coverage, which the pandemic worsened.

Although overall cases of STDs and STIs fell in the pandemic's early months, the CDC acknowledges that's likely due to the reduced frequency of in-person health care services, resulting in fewer screenings. STD test and lab supply shortages, the diversion of health workers to pandemic response teams, and lapses in health insurance due to unemployment also contributed. Plus, the pandemic came after years of cuts to public health funding.

As anticipated by many experts, numbers picked up again at the end of 2020, with other diseases like gonorrhea and syphilis surpassing 2019 levels, according to CDC data. Preliminary data from 2021 shows there were more than 2.5 million reported cases of chlamydia, gonorrhea and syphilis in that year, meaning STDs and STIs continued to increase during the second year of the pandemic too, with no signs of slowing.

The CDC says it's likely, "...we may never know the full impact of the pandemic on STDs. What is clear, however, is the state of STDs did not improve in the United States. Prevention and control efforts remain as important as ever."

But, the country's prevention and control methods need work. Comprehensive sex ed programs would be a start on prevention among the most commonly affected age group, but robust public testing and information campaigns could help all Americans. Public health funding, however, has faced slashes for years, taking a toll on STD screening and prevention efforts.

"Public funding cuts will prevent the public health system, the safety net, of being able to track down people's partners so that your index patient doesn't get reinfected because their partner was also treated appropriately," said Dr. Anna Maya Powell, co-director of the Johns Hopkins HIV Women's Program. "It's easy to say, 'People should take personal responsibility and come in for care,' but I think the picture is much more complex than that."

Only 2.5% of all U.S. health spending— about $3.8 trillion — is spent on public health and prevention programs. Last year, the Biden administration did announce a $1.13 billion investment to strengthen the disease intervention specialists (DIS) workforce at the CDC. Still, much of that funding seems to be for the agency's pandemic response.

Still, there's a reason for some optimism: There has been progressing on STDs and STIs since the HIV/AIDS epidemic of the 1980s and 90s. The STI spread rapidly in the country then, especially among certain groups, like men who have sex with other men.

Years of public information campaigns and research into treatment brought numbers down through the early 2000s and to a stable level by 2013. More recent figures may seem to hint at further progress on the overall HIV cases during the early pandemic, but those figures are also misleading because of the sharp drop in testing.

Plus, many experts have criticized the focus of historic HIV treatment and prevention efforts as largely being focused on treating rich, white, gay men and transgender groups, leaving out many lower-income Americans, people of color and women.

Women generally face a greater burden when it comes to sexual health. Many studies have established that women have a higher biological risk for contracting many STIs and HIV than men, with a higher probability of transmission from men to women.

"Women tend to be more asymptomatic for a lot of a lot of the conditions we're talking about," Dr. Powell said. "Not having symptoms maybe gives people a false sense of security, and then they don't come in to get the routine screening that they might have otherwise if things were open and accessible."

Black women, in particular, suffer higher numbers of both HIV and other STDs like herpes, and many experts say public prevention efforts have failed to address these groups adequately. Overall, inconsistent access to health care and prevention programs across different demographics throughout the country has affected our national battle against STDs and STIs.

"We have had data that shows consistently what we need to be doing in the sexually transmitted infections, those cases in reproductive health," said Dr. Mati Hlatshwayo Davis, director of health for the city of St. Louis, Missouri. "We need to make sure that those policies are as standardized as possible so that they're easily implementable and therefore easy to track data, data that then feeds back into the funding."

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Supreme Court Justice Ruth Bader Ginsburg has been discharged from the hospital after receiving treatment for a possible infection, according to Reuters and NBC.

Ginsburg was admitted to The Johns Hopkins Hospital in Baltimore on Tuesday morning. Both NBC and Reuters report that the 87-year-old Justice is "home and doing well" after the brief hospital stay.

This story is breaking and will be updated.

BROOKFIELD, IL — The reported infection of animals with COVID-19 has been documented around the world. Most have been infected after contact with their human owners or caretakers.

Veterinarians say part of the fight against the coronavirus includes vaccinating zoo animals to prevent what’s known as spillover infections.

Scientists say most emerging infectious diseases originate in animals.

In fact, the zoonotic origin of the 2003 SARS outbreak in Asia was traced back to cave-dwelling horseshoe bats in China. It eventually reached animals in live markets where it spilled over into humans.

“There's a huge interconnectedness between animals and people when it comes to a different number of different viruses and other illnesses,” said Dr. Mike Adkesson, vice president of clinical medicine at the Chicago Zoological Society

Still, the source of SARS-CoV-2 or COVID-19 is still an official mystery.

An unclassified report from the office of the Director of National Intelligence last month was only confident that it was “not developed as a biological weapon.”

What we do know is that the novel coronavirus is not a human-only infection.

“We have seen cases of COVID-19 occur in a number of different species around the country in different zoos, primarily primates, large cats such as tigers, lions, leopards, as well as a number of smaller carnivores like otters and mink,” said Adkesson.

Late last week, more than a dozen western lowland gorillas reportedly tested positive for COVID-19 at Zoo Atlanta. Their care team noticed changes in appetitive and respiratory issues.

“Coughing, sneezing, lethargy, the animals just clearly feel a little bit under the weather, the same way that we see those same signs and symptoms in people,” said Adkesson.

While animals are not playing a major part in the transmission of the virus, they are clearly susceptible.

“Part of the concern is that those animals are able to spread it to other animals and potentially able to spread it back to people,” said Adkesson.

The CDC says there have been isolated cases of domestic dogs and cats that have become infected and have been able to transmit COVID-19 back to people.

Zoos across the country are now vaccinating their animals beginning with carnivores, primates, and big cats. The emergency use authorization of the vaccine Zoetis requires two doses three weeks apart.

“We're still pretty early on in this process, but we know that the vaccine is safe from the trials that Zoetis has done with it,” said Adkesson. “So, it's really just a question of how efficacious it's going to be in the long run for our animals.”

Caretakers at the Brookfield Zoo outside Chicago have been required to mask and maintain social distancing as much as possible from the animals.

“There have been cases that have emerged in other zoos, though, even with those guidelines in place. So, we know that the virus is able to infect many of these animals the same way it's able to infect people,” said Adkesson.

It’s another reminder that the health of humans, animals, and the environment is intertwined.

By now, you’ve probably memorized all the possible ways you can get COVID-19. So if you’re feeling like a bit of an armchair infectious disease expert, you might be wondering how other illnesses in your life spread, like the flu.Sure, you’ve known practically your whole life that good hand hygiene and doing your best to steer clear of people who are sick is a good way to lower your risk of influenza. But how does the flu really spread? Is the flu airborne or not? Here’s what you need to know. What is the flu, again?The flu is a contagious respiratory illness called by influenza viruses, according to the Centers for Disease Control and Prevention. There are two main types of the flu — influenza A and B — and they cause seasonal flu epidemics each year. The flu can cause mild to severe illness, and it can cause people to be hospitalized and even die from the virus. OK, so how does the flu spread?The flu mainly spreads from person to person, and the CDC says that infected people can spread the virus to people up to six feet away. The flu usually spreads through respiratory droplets that emerge when infected people cough, sneeze or talk.Those droplets can then land in the mouths or noses of people who are nearby or be inhaled into the lungs and make them sick. Less commonly, people can get the flu from touching an infected surface or object and then touching their own mouth, nose, or eyes, the CDC says. Is the flu virus airborne?It can be, but it’s not the primary way the flu is transmitted. An airborne particle is a small particle that can remain suspended in the air for a certain period of time. Respiratory droplets are heavier and therefore fall to the ground pretty quickly after they’re expelled from a person, said Richard Watkins, M.D., an infectious disease physician and professor of internal medicine at the Northeast Ohio Medical University. The CDC says that the flu is largely spread through respiratory droplets. However, it also says airborne transmission can occur, but not over long distances, and not as commonly as via the droplets. “The flu, like many respiratory viruses, has some components of airborne spread and some components of respiratory droplets spread,” explained infectious disease expert Amesh A. Adalja, M.D., a senior scholar at the Johns Hopkins Center for Health Security. “It is really a continuum.”There are some situations where the flu is more likely to generate aerosols and become airborne, like when a person is intubated in a hospital, Adalja said. But he stresses that this is different from a highly contagious airborne virus like measles, which is primarily spread through the air. William Schaffner, M.D., an infectious disease specialist and professor at the Vanderbilt University School of Medicine, agrees. “The data would indicate this only happens under certain circumstances,” he said. “The flu is spread overwhelmingly through close personal contact.” However, the flu may be more likely to hover in the air in the winter, when the air is drier, Schaffner points out. “That little bit of fluid that covers the particles evaporates and they’re not as heavy,” he said. “That’s one of the reasons it’s thought that influenza is more common in the winter — the air is drier then.”Will COVID-19 prevention measures protect people from the flu, too?Definitely. “Mask wearing, social distancing, and hand washing are effective prevention methods for flu avoidance,” Watkins said. “Which is why last year we saw a record low number of flu cases.”“Last season, we had almost no flu and all of us were staying home, washing our hands, and wearing masks,” Schaffner said. “It all had a profound effect on reducing the influenza virus.” However, note that the COVID-19 vaccine will not protect you against the flu.What else can you do to stop the spread of the flu?Getting vaccinated against the flu is a must, Adalja said. The flu vaccine has been shown to reduce flu-related illnesses and the risk of complications that can lead to hospitalization and death, the CDC points out. Some other tips from the CDC: Stay away from people who are sick Cover your coughs and sneezes Wash your hands oftenIf you’re high risk for flu complications, Schaffner recommends doing your best to practice social distancing when influenza is circulating in your community. “Maybe rent a movie instead of going to a movie,” he said.

CNN —

Related video above: Doctor answers COVID-19 vaccine questions

Health experts have said that data so far has shown that COVID-19 vaccines prevent symptoms of the virus — but a new study suggests that the Moderna and Pfizer vaccines may also prevent infections.

A team at the Mayo Clinic health system looked at more than 31,000 people across four states who had received at least one dose of either vaccine — and found their vaccines were upwards of 80% effective in preventing infection 36 days after the first dose.

Vaccine efficacy was 75% 15 days after the first dose, and appeared 89% effective from 36 days after the second dose, according to the research, which has not yet been peer-reviewed.

Despite a backlog in inoculations due to harsh winter weather that has gripped much of the U.S., officials have been pressing to vaccinate Americans before what appear to be more transmissible variants, which they fear could reverse the progress in terms of lowering cases and hospitalizations.

More than 59 million vaccine doses have so far been administered in the U.S., according to data from the U.S. Centers for Disease Control and Prevention.

But Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington, said Friday that the U.S. is unlikely to achieve herd immunity for the virus before the winter.

"We know COVID is really seasonal, so when the next winter rolls around, we need to have a much higher level of protection to stop COVID in its tracks than we are likely to achieve," he said.

Herd immunity doesn't take effect until 80% or more of the population has immunity, either through infection or vaccination. And the new variants may complicate the picture, Murray said. If people can be reinfected with the new variants, the pandemic may take off again.

Though officials hope to have vaccines widely distributed by the end of the summer, President Biden said Friday that issues like weather, mutating strains and manufacturing delays make it hard to nail down a timeline.

"I believe we're on the road, I promise you. I know we'll run into bumps. It's not going to be easy here to the end, but we're going to beat this. We're going to beat this," he said while visiting a Pfizer facility in Michigan.

Too risky to give single doses, Fauci says

One way to protect more people quickly, some experts suggest, is to prioritize administering first doses of the vaccine.

Dr. Ashish Jha, Dean of the Brown University School of Public Health, advocated Friday for U.S. officials to consider delaying the second dose.

"Would that really be a problem, because if we could do that, we could vaccinate a lot more high-risk people, quickly...Everybody needs a second dose, but I think we can do it in a way that's still safe and get a lot more people protected," Jha told CNN.

But Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, said Friday that a single-dose plan would be too risky.

Fauci said he worried that if large numbers of people got a single shot and had less than optimal immune responses, they could be exposed to the virus and start incubating viral mutations. In theory, new variants could arise, he said.

"We will stick with the scientifically documented efficacy and optimal response of a prime followed by a boost with the mRNA vaccines," Fauci told a White House briefing.

Jha, for his part, said he agreed that everybody needed a second dose, "I think the question is, right now we wait four weeks between first and second dose. What if we went six weeks or eight weeks or 10 weeks — not much longer than that."

School can reopen now matter the virus' spread, CDC director says

In the hopes of returning to some sense of normalcy, a priority to many families and officials has been allowing students to resume in-person learning.

And CDC Director Dr. Rochelle Walensky said Friday that given the right precautions, schools may open no matter how much virus is spreading in the community.

As of Tuesday, CNN analysis indicated about 90% of children live in so-called red zones under the CDC's guidance — meaning there is a high level of community spread of the virus. But even in those conditions, schools can safely reopen if they take precautions, Walensky told a White House briefing.

The CDC has said schools can reopen if they make sure they are mitigating the risk of spread with universal mask use, measures to keep children and staff six feet apart, frequent cleaning and disinfection and testing and contact tracing.

The CDC director's assurances came as Fauci announced that the U.S. should have vaccine safety data for high school-age kids by the beginning of fall.

Companies are just starting tests of younger age groups but have been testing their vaccines on 12- to 17-year-olds, Fauci told a White House briefing. Safety data for younger children will likely not be available until early next year, he said.

Vaccine hesitancy not an excuse for inequities

Meanwhile, vaccine trials and distribution have shed light on inequities in the medical field.

People of color have been vastly underrepresented in U.S.-based vaccine trials for the last decade, according to a new study released Friday by researchers at Fred Hutchinson Cancer Research Center, Harvard, Emory and other institutions.

The study found that white people made up the majority, or 78%, of participants in trials conducted between June 2011 and June 2020.

The study, published in the JAMA Network Open, comes as the nation grapples with a pandemic that has disproportionately impacted people of color. Health care leaders are working to combat vaccine distrust among Black and brown people, saying the shot is the key to preventing further devastating in their communities.

But that hesitancy should not be an excuse for officials to explain away racial disparities in vaccination, Fauci said.

"It's that we've got to really extend ourselves into the community to get the access to minority populations that they don't have," Fauci said in an interview with MSNBC.

CHICAGO, Ill. — Canceled last year, Lollapalooza made its return this week. The annual four-day music festival is expected to draw 100,000 people. It’s one of the first giant events in the country since the pandemic began. More are planned in the coming months including Bonaroo, the Governor’s Ball, and Summerfest.

Despite health checks, some in public health are watching this event closely, concerned a head-on collision with the delta variant could turn the outdoor concert event into a super spreader event.

Still, following months of isolation, tens of thousands have flocked to Chicago’s Grant Park to escape the pandemic and enjoy outdoor music.

“It's my second time out at Lollapalooza,” said Kevin Metras, a Lollapalooza attendee. “I'm so excited. It's nice, hot. You know, I'm trying to sweat and stay hydrated.”

It’s the first major music festival in the U.S. since the outbreak began. But it comes at a time when COVID-19 cases are surging in parts of the country.

“You know, I got my vaccine, I'm young, I'm healthy, I think I should be OK,” said Ishi Nagpal, a Lollapalooza attendee who chose not to mask.

Yet, guidelines to attend Lolla were recently loosened.

At first, proof of full vaccination or a negative COVID-19 test 24 hours before entering each day was required. That was downgraded to within 72 hours of arrival.

“No, we're all going to die either way,” said Lollapalooza attendee Kailee Parker

Masks are mandated for all unvaccinated attendees, but it’s unclear how that’s going to be enforced once you get past the gates.

“Yeah. You know, probably when I’m within the groups of people I probably might wear it a little bit,” said Metras, who is wearing a mask. “It just makes us all feel good. I'm vaccinated but, you know, gotta take that extra step sometimes.”

“The Lollapalooza organizers haven't really made good on their promise to use electronic apps to track vaccination and testing. And so far, ticket holders haven't had to upload those things,” said Dr. Emily Landon, an infectious disease specialist at the University of Chicago Medicine.

A busy Fourth of July weekend resulted in a cluster of COVID-19 cases in Provincetown, Massachusetts. There were more than 830 cases. About 74% of them were reportedly breakthrough infections among vaccinated visitors who became symptomatic.

“I can't promise that there won't be any COVID cases associated with Lolla when you're having this many folks who are coming through,” said Dr. Allison Arwady, commissioner of the Chicago Department of Public Health. “Almost certainly there will be some cases.”

City public health officials admit there are risks of COVID-19 spreading even outdoors at massive gatherings like Lollapalooza, but remained confident that they’ve taken proper precautions.

“I'm certainly hopeful that we won't see a significant problem. And I certainly know we're being a lot more responsible than many other settings,” said Arwady.

But unlike barriers and fencing, what happens on these grounds can’t be contained.

“The one thing that will make Lollapalooza into a really dangerous event for the rest of this country will be if people leave Lollapalooza, go back to their unvaccinated communities and ignore the symptoms that they have afterward,” said Landon.

Some infectious disease experts recommend getting tested after attending massive outdoor festivals, especially if you experience any symptoms.

“We're planning on getting tested a few days after just in case, you know, you can never be too careful,” said Cassie Cabanas, a Lollapalooza attendee who is wearing a mask even though she is vaccinated.

But some experts say there’s only one real way to side-step the threat.

“If you don't want to get COVID, don't go to Lollapalooza,” said Landon.

Experts say contact tracing across state lines will be key in assessing the ripple effect of mass gatherings like Lollapalooza. The results could also set the stage for health protocols at other major festivals.

A new study has found evidence that SARS-CoV-2, the virus that causes COVID-19, infects the cells in the mouth including the salivary glands — which may explain some COVID-19 symptoms such as loss of taste and dry mouth.

The findings of the study led by the U.S. National Institutes of Health (NIH) and the University of North Carolina at Chapel Hill also “point to the possibility that the mouth plays a role in transmitting SARS-CoV-2 to the lungs or digestive system via saliva laden with the virus from infected oral cells,” according to a press release.

The study, published in Nature Medicine, focused on discovering where SARS-CoV-2 in the saliva comes from as it is well established that people diagnosed with COVID-19 contain high levels of the virus in their saliva.

People with COVID-19 who have respiratory symptoms may have the virus in their saliva from nasal drainage of sputum coughed up from the lungs, the release states, but the researchers said it may not explain how the virus gets into the saliva of people who lack those symptoms.

Blake Warner, lead study author and assistant clinical director and chief of the National Institute of Dental and Craniofacial Research (NIDCR), said in the release that “based on the data from our laboratories, we suspected at least some of the virus in saliva could be coming from infected tissues in the mouth itself.”

To investigate this, scientists surveyed oral tissue collected from healthy people in order to identify mouth regions susceptible to SARS-CoV-2 infection. The vulnerable cells contained ribonucleic acid (RNA) molecules that have instructions for making “entry proteins” or “doorways” that the virus needs to be able to get into the cells and infect it.

RNA for two key entry proteins known as the ACE2 receptor and the TMPRSS2 enzyme were found in cells of the salivary glands and in tissues lining the oral cavity, which indicated “increased vulnerability because the virus is thought to need both entry proteins to gain access to cells,” the release states.

Warner said that those factors are similar to the ones found in regions known to be susceptible to SARS-CoV-2 infection, such as the lining of the nasal passage and upper airways.

The next step for the researchers after confirming that parts of the mouth are susceptible to SARS-CoV-2 was to look for evidence of infection in oral tissue samples from people with COVID-19. In samples collected at the NIH from COVID-19 patients who had died, SARS-CoV-2 RNA was found in “just over half” of the salivary glands examined. Researchers also found the specific sequences of RNA that indicated cells were actively making new copies of the virus in a living person who had acute COVID-19.

The study further found that salivary gland tissue infected with SARS-CoV-2 could be the source of the virus in saliva. In people with mild or asymptomatic COVID-19, cells shed from the mouth into saliva were found to have the RNA entry proteins and SARS-CoV-2 RNA.

In order to determine whether virus found in saliva is infectious, researchers took saliva from eight people with asymptomatic COVID-19 and exposed it to healthy cells grown in a dish.

Saliva from two of the eight subjects led to infection of the healthy cells – raising the possibility that asymptomatic COVID-19 patients might transmit infectious SARS-CoV-2 to others through saliva, according to the study.

A final aspect of the study was to explore the relationship between oral symptoms of COVID-19 and virus in saliva. Researchers collected saliva from a group of 35 volunteers with mild or asymptomatic COVID-19. Of the 27 people who were experiencing oral symptoms, those with the virus in their saliva were more likely to report loss of taste and smell, suggesting that oral infection might underlie oral symptoms of COVID-19.

The study’s findings suggest that the mouth, via infected oral tissue cells, plays a bigger role in SARS-CoV-2 infections than previously thought.

“When infected saliva is swallowed or tiny particles of it are inhaled, we think it can potentially transmit SARS-CoV-2 further into our throats, our lungs, or even our lungs,” said Kevin Byrd, second author of the study and assistant professor in dentistry at the University of North Carolina Chapel Hill, in the release.

The researchers hope to confirm their findings in a larger group of people and to determine the exact nature of the part the mouth plays in SARS-CoV-2 infection and transmission, according to the release.

"By revealing a potentially underappreciated role for the oral cavity in SARS-CoV-2 infection, our study could open up new investigative avenues leading to a better understanding of the course of infection and disease. Such information could also inform interventions to combat the virus and alleviate oral symptoms of COVID-19," Warner said.

It may feel like the U.S. is beginning to return to pre-pandemic times, but in parts of the world, COVID-19 cases are still very high.

The director-general of the World Health Organization warned people the virus is still a threat.

"It would be a monumental error for any country to think the danger has passed," Tedros Adhanom Ghebreyesus said.

"The tailored and consistent use of public health measures in combination with equitable vaccination remains the way out."

He also called on countries to work together to end the pandemic and prepare for the next one.

He proposed a treaty on pandemic preparedness and response.

This story originally reported by Alex Livingston and Eliana Moreno on Newsy.com