Zoonotic, non zoonotic and reverse zoonotic diseases

Updated Jan 25, 2025 | 08:00 AM IST

Is There A Difference Between Zoonotic, Non-Zoonotic And Reverse Zoonotic Diseases

SummaryNot all animal diseases are zoonotic diseases, some are zoonotic, some are non-zoonotic, and some are reverse zoonotic diseases. But, what are the difference?

We have all, by now, know that while 2024 was a year disease, but 2025 awaits even more. At the starting of the year only we saw a rise in the cases of bird flu, and saw the virus spread among people too. Then there was trichomoniasis in birds in the UK, and FMD in Germany, and many more. While the source of it all might be animal, not all of these are zoonotic diseases. Not all animal diseases are zoonotic diseases, some are zoonotic, some are non-zoonotic, and some are reverse zoonotic diseases. But, what are the difference?

What Are Zoonotic Diseases?

Zoonotic diseases or zoonoses are infectious diseases that can be spread between animals and humans. It originated with the domestication of animals, animal products or animal derivatives. The word also stems from the Greek word zoion, which means animal, and nosis, which means diseases.

The term was first used in 1885 by Rudolph Virchow in his Handbook of Communicable Diseases. It spreads between vertebrates and humans, which means animals with a backbone, and birds. The way their bodies work is similar enough to ours that pathogens can sometimes adjust to live in both.

While some zoonotic diseases spread only from animals to humans and do not spread from person to person. There are other diseases like Ebola, Mpox, COVID-19, and many more which come from animals, but continue to spread in humans, through humans, and cause outbreaks. Some of them also spread in humans and then mutate to infect only humans, like HIV

Many pathogens are limited to infecting a single type of host—humans, specific animals, plants, or even other microorganisms. However, zoonotic diseases are unique because they can infect both humans and other vertebrates. In some cases, these diseases originally affected only animals, but genetic mutations enabled them to "jump" to humans and cause infections.

Zoonotic illnesses are typically caused by bacteria, parasites, or viruses. However, they can also stem from other sources, such as fungal infections like ringworm or prion diseases like variant Creutzfeldt-Jakob disease (vCJD), often referred to as “mad cow disease.” Animals that carry zoonotic diseases:

  • Bats
  • Birds
  • Cats
  • Deer
  • Dogs
  • Livestock
  • Non-human primates, monkeys, apes and chimpanzees
  • Rodents

What Are Non-Zoonotic Diseases?

Not all animal diseases are zoonotic. Zoonoses are infectious diseases that can transfer between animals and humans such as rabies, anthrax, influenza, Nipah, COVID-19, brucellosis, and tuberculosis. However, not all animal diseases are zoonotic. Many diseases affect livestock without posing a risk to human health. These non-zoonotic diseases are species-specific and cannot infect humans. Examples include Foot & Mouth Disease (FDM), PPR, Lumpy Skin Disease, Classical Swine Fever, and trichomoniasis in birds and animals.

What Are Reverse Zoonotic Diseases?

It is the case where a disease transmits from humans to animals. This also poses threats to animals health as well as public health, due to the potential for animal disease reservoirs to form.

In 2020, several mink farms in the Netherlands experienced a severe respiratory disease outbreaks, upon investigation, it was revealed that minks had been infected with SARS-CoV-2, the same virus responsible for COVID-19. The minks came in contact with infected farmworkers.

There have been cases when domesticated dogs, cats and ferrets have developed flu-like symptoms caused by influenza A virus, passed on by their owners. Human-derived pathogens also pose significant risks to endangered wildlife. For example, in Tanzania, an outbreak of human metapneumovirus resulted in fatalities among a population of wild chimpanzees. The virus was believed to have been transmitted by researchers and visitors to the national park where the chimpanzees lived, highlighting the potential consequences of human-wildlife interactions.

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Bryan Johnson Says Botox and Shockwaves Improved His Nighttime Erections by 34%

Credits: Instagram & Wikimedia Commons

Updated Apr 26, 2025 | 02:00 AM IST

Bryan Johnson Says Botox And Shockwaves Improved His Nighttime Erections By 34%

SummaryBiohacker Bryan Johnson uses Cialis, shockwave therapy, and Botox to boost nighttime erections, claiming they reflect overall health and aging — aiming for the vitality of an 18-year-old.

In mid-2023, the tech mogul and self-proclaimed biohacker, the anti-age crusader Bryan Johnson began a new chapter in his longevity journey. He is already known his extreme anti-aging regimen - Project Blueprint. He has turned his attention to something unconventional. However, it is a telling health metric: nighttime erections.

He has now started a daily dose of 2.5mg of tadalafil (Cialis). He has set out to track and enhance what he calls a crucial "vital sign". His goal is not performance, but optimization. He tells his followers on X, the results were "titanic".

By early 2024, Johnson had added focused shockwave therapy and Botox injections to the mix. Within three months, he says, his nighttime erections improved by 34%. It has clocked in at quite an impressive three hours, with biological equivalent of an 18-year-old.

It Is Not Just About Sex

While the idea of three-hour erections may sound like a punchline, Johnson is pretty serious about it. "Nighttime erections," he explains, "are a strong biomarker of cardiovascular, psychological, and sexual health." These spontaneous erections during sleep can reflect a man’s overall physical and vascular health.

What is interesting to see is that he also maintains that Cialis itself is unlikely to be the sole driver of his sexual function improvements. While the drug is FDA-approved to treat erectile dysfunction, Johnson says it mainly supports long-term health. His claims are that it helps with improved heart function, cognitive health, and reduced urinary symptoms in men.

The Therapy Protocol

In order to push his results further, Johnson also turned to shockwave therapy. This is a treatment that involves acoustic pulses delivered via a wand to the penis.

The shocks cause micro-injuries that stimulate blood flow and tissue repair - not unlike how muscles grow after a workout. However, it is not a spa day. Johnson rated that the pain is 7 on a scale of 10. When it is "at the tip", the pain goes up to 9 on a scale of 10.

Alongside the shockwaves, Johnson began Botox injections, which might sound bizarre but are backed by emerging science. Botox, typically used to reduce facial wrinkles, is thought to relax the smooth muscle in blood vessel walls, allowing more blood flow and potentially firmer erections.

ALSO READ: The Longevity Diet: Bryan Johnson Eats 3 Meals In 6 Hours—With Extra Virgin Olive Oil

What Are The Results Like?

After three months on this combined protocol, Johnson says his nighttime erections rose from 2 hours and 15 minutes to 3 hours. Despite the gains, he reportedly sleeps alone, keeps an 8:30 p.m. bedtime, and schedules sex, if at all.

His larger aim? To maintain all his organs — brain, liver, teeth, even his rectum — at peak teenage condition through strict diet, 111 daily supplements, and intensive routines.

While Johnson’s methods are extreme, he hopes they help reduce stigma. “Men, if you’re not performing how you’d like, there are many paths to improvement,” he said. “There’s no shame in this — in fact, it will make you more of a man to address it head-on.”

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Why Its Important To Check The Expiry Date On Your Pregnancy Test?

Updated Apr 25, 2025 | 10:00 PM IST

Why Its Important To Check The Expiry Date On Your Pregnancy Test?

SummaryPregnancy tests detect the hormone hCG in urine and are up to 99% accurate when used correctly, but using an expired test can lead to false results and delayed care.

If you're trying to conceive or even think you might be pregnant, the wait and anticipation for a pregnancy test can be nerve-wracking—hope, worry, excitement, or fear all in one little plastic stick but before you rip open that foil package, there's something important you may be forgetting: the expiration date.

Yes, pregnancy kits do have expiry dates. And taking one which has passed that date may cause false results. This article touches on why checking that date on the kit first is important before you test, how pregnancy kits work, and what dangers such expired kits possess. Supported by expert opinion and scientific knowledge, this guide endeavors to equip you with the knowledge you require for making informed reproductive health choices.

Home pregnancy tests detect the human chorionic gonadotropin (hCG) hormone in your urine, which your body begins making shortly after the fertilized egg implants in your uterus. The test sticks use special antibodies with chemicals that have been treated to respond to hCG and report a positive finding—usually lines, plus symbols, or messages on a display.

With time, though, the delicate components break down. After the test has reached or exceeded its expiration date, the chemical reagents can no longer act dependably. That is, the test might not register hCG when it's actually there, providing you with a false negative result, or—much less often—report a false positive based on poor chemical reactions.

What Happens When a Pregnancy Test Expires?

The date of expiration on a pregnancy test is not merely a courtesy. Companies test their products extensively to find out how long the ingredients will be stable and consistent under normal storage conditions. A pregnancy test will usually be effective for one to three years from the date of manufacture.

Once that time has passed, the antibodies that are employed to identify hCG start to weaken. This weakening is subtle but significant—making the test incapable of giving accurate results. The older the test, the greater the likelihood that you'll leave with a result that doesn't accurately represent your pregnancy status.

Just as important as the expiration date is how the test is stored. According to healthcare professionals, the performance of a pregnancy test can deteriorate even before its listed expiry if it’s stored improperly.

Avoid exposing the test to heat, moisture, or direct sunlight. A bathroom medicine cabinet, while convenient, is often not ideal due to the humidity from showers and temperature fluctuations. Instead, keep pregnancy tests in a cool, dry place, and avoid unwrapping individual tests until you’re ready to use them. Unsealing the protective foil can introduce air and moisture that degrade the chemicals faster.

How to Identify an Expired Test?

Always inspect the outer package and test wrapper individually for a printed expiration date. If it is absent or smudged, better not take a risk. Also, beware of buying tests from third-party retailers or online stores where expired stock may go unnoticed.

It's also good to know that even tests just purchased can be old inventory. If you've had a test kit in your bathroom drawer for more than one year, verify the printed date before you use it.

Can You Trust an Expired Test?

Technically, it's possible for an outdated pregnancy test to return a correct result—but it's not reliable. The odds of false negatives grow more sharply with time, which can cause confusion, worry, and delay in obtaining critical prenatal care.

Under FDA recommendations, most erroneous results from past-due tests are likely to be false negatives. This may lead one to continue habits or drugs that are not best practiced in early pregnancy—or lose the opportunity to start early prenatal supplements or tests.

The effect of depending on an out-of-date pregnancy test isn't only medical—it's psychological as well. Inaccurate results can induce undue distress, confusion, or early rejoicing. Even worse, they may stall time-critical health choices like verifying the pregnancy through a physician, making blood work appointments, or starting lifestyle modifications to facilitate a healthy pregnancy.

In medical situations where time is of the essence—like watching over high-risk pregnancies or starting specific treatments—true, timely information is paramount.

Best Practices for Taking a Home Pregnancy Test

To ensure most accurate results, follow these steps:

  • Inspect the expiration date before taking any test, even if the package appears new.
  • Take first-morning urine when hCG is most concentrated in the urine.
  • Wait until the first day of your missed period to take the test; testing earlier riskily produces a false negative.
  • Take directions exactly, including timing when to read the results.
  • Dispose of unused tests properly, in a dry, cool environment and in their original sealed package.

How Expired Pregnancy Tests Impact Health and Results?

Taking an expired pregnancy test can result in incorrect results, which might lead to undue confusion or undue delay in taking the appropriate next step. Here's what you should know regarding the effectiveness of an expired pregnancy test:

Increased Chance of False Negatives

One of the most significant problems with using an outdated pregnancy test is the increased likelihood of getting a false negative result. This is where the test will show that you're not pregnant when you actually are. This is due to the chemical compounds, especially the antibodies employed to identify hCG, breaking down over time, thus it becomes hard for the test to give a true result.

Degraded Antibodies

Pregnancy tests detect human Chorionic Gonadotropin (hCG), a hormone that is formed during pregnancy. After a while, the antibodies in the test, which cause a response when hCG is present, become weakened. So even if you are pregnant, the test may fail to measure the hormone at a level that is high enough.

Health Risks

As per the U.S. Food and Drug Administration (FDA), expired pregnancy tests tend to give false negatives rather than false positives. A false positive may also occur but is less so with expired tests.

Exposure to External Factors

The reliability of a pregnancy test is also affected by the way it's stored. Incorrect storage, for example exposure to sunlight, humidity, or heat, causes the components to degrade faster and results in more opportunities for getting incorrect results prior to reaching expiration.

Waste of Time and Money

Using an expired test not only reduces the likelihood of getting an accurate result but also wastes your time and money. It's best to check the expiration date before using the test and, if expired, purchase a new one for peace of mind and more reliable results.

Emotional Stress

The effect of depending on an out-of-date pregnancy test isn't only medical—it's psychological as well. Inaccurate results can induce undue distress, confusion, or early rejoicing.

Though home pregnancy tests are an efficient and convenient means of early pregnancy detection, their accuracy relies on a number of major factors, foremost among them their expiration date. Testing with one that has expired may cause emotional distress and delay medical attention at a time when it's needed most.

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Fearing Mosquitos? Malaria Can Be Spread Through Blood Transfusion Also

Credit: Canva

Updated Apr 25, 2025 | 09:00 PM IST

Can You Get Malaria Without Mosquito Bite?

SummaryMalaria is a vector-borne disease. It is spread through female anopheles mosquitoes. These mosquitoes carry single-cell P. Falciparum, which is a pathogen behind this disease.

Malaria is a life-threatening disease that is spread to humans by a specific type of mosquito. It is preventable and curable, but only if detected on time. People who are at high risk include travellers, pregnant women and those with HIV/AIDS. On Friday, while marking World Malaria Day, the World Health Organisation (WHO) asserted that half of the total global population is at risk of this vector borne disease. So now, the question arises: how does it spread?

Malaria is a vector-borne disease. It is spread through female anopheles mosquitoes. These mosquitoes carry single-cell P. Falciparum, which is a pathogen behind this disease. There are five types of Plasmodium parasite, with P. Falciparum (which is found in the African region) and P. Vivax ( common outside the sub-Saharan region) being the most popular. Left untreated, P. Falciparum malaria can progress to severe illness and death within 24 hours.

Malaria Can Be Spread Through Blood Transfusion

But there is empirical evidence that it can also be transmitted through blood transfusion and contaminated needles. Transfusion-transmitted malaria (TTM) occurs when an uninfected person receives blood from a donor who is infected with malaria parasites. While malaria transmission through transfusion is rare, especially in non-endemic areas, it remains a significant concern in certain regions.

According to a systematic review of studies conducted by National Library of Medicine, Plasmodium parasites were shown to survive in whole blood and plasma when stored at 4°C for up to 18 days, and detectable parasites can present even up to 28 days when frozen, although with diminished infectivity.

How To Identify Malaria?

The early symptoms of Malaria are fever, headache and chills, which can usually start within 10 to 15 days of getting bitten by an infected mosquito. Some types of malaria can cause severe illness and death. Infants, children under 5 years, pregnant women, travellers and people with HIV or AIDS are at higher risk. Severe symptoms include:

  • extreme tiredness and fatigue
  • impaired consciousness
  • multiple convulsions
  • difficulty breathing
  • dark or bloody urine
  • jaundice (yellowing of the eyes and skin)
  • abnormal bleeding
People with severe symptoms should get emergency care right away. Getting treatment early for mild malaria can stop the infection from becoming severe. Malaria infection during pregnancy can also cause premature delivery or delivery of a baby with low birth weight.

Disproportionate Share Of Global Malaria Burden

The WHO African Region continues to carry a disproportionately high share of the global malaria burden. In 2023, the region was home to about 94% of all malaria cases and 95% of deaths. Children under 5 years of age accounted for about 76% of all malaria deaths in this region. Over half of these deaths occurred in four countries: Nigeria (30.9%), the Democratic Republic of the Congo (11.3%), Niger (5.9%) and United Republic of Tanzania (4.3%).

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