Covid-19 summer wave, peak mosquito season, two Cyclospora deaths (and the outbreak calming down), and more
The Dose (August 4)
Somehow we’re already in August. I love my kids dearly, but let the countdown to school (and routine) begin!
August also brings some health news: peak mosquito season, a summer Covid-19 wave, and thankfully, signs that the explosive diarrhea outbreak is calming down—but not without two deaths, reported yesterday. August also means midterms are around the corner, and I have a hunch that some narratives, like Covid-19 pandemic revisionism, are strategic. We include some tips for your blood pressure.
Here’s your “disease weather report”, and most importantly, what you can do other than get into social media fights about Covid-19.
Covid-19 chatter and a summer wave
Whether it’s mass media or social media, there’s a lot of loud, recent chatter about the Covid-19 pandemic. I’ve been struck by the timing, as well as how disciplined much of the messaging has been from politicians. I can’t help but wonder if this is a strategic distraction ahead of the midterms. As I’ve said over and over, it’s critically important to talk about what went wrong and what went right during the pandemic, but only if it’s in good faith. What I’m seeing instead is the reopening of deep, traumatic wounds of a complex event that’s already one of the most polarizing in this country.
What this means for you: Our social media consumption is controlled through a powerful algorithm. Attention is the currency being harvested here, so one of the strongest moves is deciding in advance what you simply will not spend it on. This is called critical ignoring. If you do engage, which I sometimes think is necessary to tell our own truths, try to stay earnest. Pushing back without taking the bait is a hard task, but I gave it my best shot on YLE socials yesterday.
Speaking of Covid-19, a summer wave continues to brew. We get this every year; the question is how high it will get, as the severity of each wave has declined over time.
Right now, rates are still very low, but all metrics (emergency visits, test positivity rates, and wastewater) are climbing across the country. There’s not a newly emerged variant really driving this, but rather a mix of seasonality and waning immunity, since it’s been a while since many people were last infected.
What this means for you: If you’re 65 or older and didn’t get your spring Covid-19 shot, the time is now.
Cyclospora outbreak hitting the breaks
We’re now up to more than 17,000 cases across the country, and it looks like things are slowing down (although the true number of cases and direction remain nearly impossible to know given our fragmented data infrastructure in the U.S.). One data point—share of tests coming back positive—is in a nosedive, which is a great sign.
While millions of Americans get all different types of foodborne illnesses each year, this outbreak is the third-largest in history. Truly a magnificent size.
What’s causing the slowdown? For Cyclospora, this usually means the main culprit has been removed from circulation. That can happen naturally (contaminated salad gradually gets replaced by clean salad) or through intervention (stores pull it from shelves). We’re heading into the second week of the recall, so hopefully that’s helped a lot.
There are still six active investigations:
Shredded lettuce with an epicenter in Michigan and a recall in 27 states. Unfortunately, Michigan reported two deaths that are likely tied to that. Deaths from cyclosporiasis are extremely rare, and I was very surprised to hear this. They were high risk (like immunocompromised after an organ transplant), so extreme dehydration could have an impact.
Five other active investigations have no other information. We don’t know what’s causing them and where. We may never get an answer, though, as this parasite is hard to trace and find. In the past, there were definitely outbreaks where the culprit was never found.
What this means for you: Shredded lettuce is likely in the clear now, but if you’re at higher risk and live in one of the 27 states under recall, I’d still stay cautious. Michigan will announce when its outbreak is under control, and that will be your all-clear signal.
August is the peak mosquito-borne illness season
Welcome to mosquito-borne illness month. West Nile virus is the most common mosquito-borne disease in the U.S. (though it’s still very rare compared to other things trying to kill you).
CDC has warned that this year is more intense than usual for West Nile virus, with case counts roughly five times the historical average. This is the earliest and most aggressive start to the season since 2004, a year that ended with 2,500 cases and 100 deaths nationally. Interestingly, West Nile tends to peak in humans on a roughly three-year cycle, driven by shifting immunity levels in birds, the virus’s primary reservoir.
August is peak season, so expect cases and news to continue popping up across the country.
What this means for you: Overall risk of mosquito-borne illnesses in the U.S. remains extremely low, and for most people, mosquitoes are more of a nuisance than a threat. Prevention is the name of the game. Here are some tips.
Spotlight: Why some people get more mosquito bites than others
Do you ever wonder why some people (hi, it’s me) end up covered in bites while the person sitting right next to them has none? That’s not by accident. The number of bites you get depends on, sure, how much of your skin is showing, but there’s some fascinating biology at play here, too:
The bacteria on your skin. Everyone’s skin is covered in bacteria, and the exact mix depends on your genes and your diet. Scientists have found that people carrying certain types of bacteria, especially those with less bacterial diversity, emit odors that mosquitoes love. People with a wider variety of bacteria tend to attract fewer bites. Even things like eating garlic or drinking alcohol have been linked to smellier, more mosquito-friendly skin.
The carbon dioxide you breathe out. Mosquitoes can sense CO2 from over 100 feet away using special sensors near their mouths. This helps them find something to bite. People who breathe out more CO2, like adults compared to kids, or anyone right after exercise, are easier for mosquitoes to track down.
Some people really do “smell better” to mosquitoes. Up close, mosquitoes also detect chemicals in your sweat, such as lactic acid and uric acid. These amounts are different for everyone. Studies on twins even suggest this trait can be passed down from your parents, meaning some people are just born more attractive to mosquitoes than others.
The same old advice still holds for these people: use DEET, picaridin, or IR3535 repellents. They work by blocking the sensors mosquitoes use to detect CO2 and skin odor, making it harder for them to find you in the first place. Citronella candles, unfortunately, have only a mild, short-range effect at best.
Good news
The OMB grantmaking rule may be facing a new hurdle. Several weeks ago, we wrote about a proposed OMB rule that could break science. This week, in bipartisan agreement, the Senate Appropriations Committee included language that would block the rule from taking effect until the next budget date. Thanks to everyone who submitted comments and organized around this. This is a critical step that buys more time to push for the rule’s full withdrawal. (Politico)
Using enzymes to “shred” cancer. Scientists at the University of Utah have found a CRISPR enzyme with an odd ability to shred specific RNA. The enzyme can be programmed to recognize a specific kind of mRNA, so it could be used to eliminate mRNA produced by a cancer cell. This treatment still has a long way to go before it can be used, but it could be very beneficial in targeting cancers that do not respond well to chemotherapy and other treatments. (Nature)
Hi-tech eye implant approved for use in Europe. The PRIMA implant is a new eye implant designed to help address common causes of age-related vision loss. It stimulates cells on the retina by converting light signals using a special pair of glasses. In the study, the PRIMA implant significantly restored vision in the majority of participants. (Ophthalmology Times, NEJM)
Bottom line
Happy August! It’s going to keep us on our toes, but the good news is that we can all do something to protect ourselves.
Love, YLE
Your Local Epidemiologist (YLE) comprises a team of experts, ranging from physicians to immunologists to epidemiologists to nutritionists, working together with one goal: to “translate” ever-evolving public health science so that people are well-equipped to make evidence-based decisions. The YLE suite of newsletters reaches over 475,000 people across more than 132 countries. This newsletter is free to everyone, thanks to the generous support of fellow YLE community members. To support the effort, subscribe or upgrade below:
Thank you for this update. In regards to Covid 19, have you heard anything on whether the vaccines will be updated this fall and what timing would be for an updated vaccine?
Your point by point response to RFK's delusional lies was absolutely fantastic. I only hope it has an impact on something or someone!