Do you know who can donate blood to you or who can you donate blood to? Blood donation may not be complex, but it does need to be compatible with yours and vice-versa. The blood types are determined by the presence or absence of certain antigens - substance that can trigger immune response if they are foreign to the body.

There are four major blood groups which are determined by the presence or absence of two antigens, A and B, on the surface of red blood cells. There is also a protein called the Rh factor, which can either be present (+) or absent (-), which creates A+, A-, B+, B-, O+. O-, AB+, AB- blood types.

Group A blood type has only A antigens on red blood cells and B antibody in the plasma. B has only B antigen on red cells and A antibody in the plasma. AB has both A and antigens on red cells, but neither A nor B antibody is present in the plasma. O has neither A nor B antigens on red cells, but both A and B antibody are present in the plasma.

Blood Type And Who Can You Donate To?

Your blood type determines who can you donate to. This is because there are very specific ways in which blood types must be matched for safe transfusion. The right blood transfusion could actually save you, while the wrong one could be lethal. Also, Rh-negative blood is given to Rh-negative patients and Rh-positive or Rh-negative blood can only be given to Rh-positive patients.

If you are O blood type, you can donate to O, A, B, and AB, if you are A blood type, you can donate to A and AB, if you are B blood type, you can donate to B and AB, however if you are AB, you can only donate to AB.

Who Can You Receive Blood From?

If you are O blood type, you can only receive from O. If you are A, you can receive from type A and O. If you are blood type B, you can receive from type B and O. If you are AB, you are lucky, you can receive blood from O, A, B, and AB.

There are more than 600 other known antigens, the presence or absence of which creates "rare blood types". Certain types are unique to specific ethnic or racial groups, this is why an African-American blood donation can be the best hope for the needs of patients with sickle cell disease, as per the Red Cross Organization.

Universal Blood Donor

Type O is one in high demand, as it can donate blood to anyone. O negative blood type is the universal blood type, which can donate to everyone, especially during the emergency transfusions and for immune deficient infants.

Who Have These Blood Types In US?

In the US, 37% Caucasian, 47% African-American, 39% Asians, and 53% Latino-American are O-positive. However, only 8% of Caucasian, 4% of African-American, 1% Asian, and 4% Latino=Americans are O-negative.

A+: 33% Caucasian, 34% African-American, 27% Asian, 29% Latino-American

A-: 7% Caucasian, 2% African-American, .5% Asian, 2% Latino-American

B+: 9% Caucasian, 18% African-American, 25% Asian, 9% Latino-American

B-: 2% Caucasian, 2% African-American, .4% Asian, 1% Latino-American

AB+:3% Caucasian, 4% African-American, 7% Asian, 2% Latino-American

AB-: 1% Caucasian, .3% African-American, .1% Asian, .2% Latino-American

Doctors in India’s southern state of Tamil Nadu surgically removed a fully developed canine tooth from the upper eyelid region of a 16-year-old boy. They described the case as the first reported instance of an ectopic tooth in the upper part of the eye socket.

The case was reported by specialists at Aravind Eye Hospital in Madurai in the journal Ophthalmology.

What Did The Doctors Find?

The teenager visited the hospital with painless swelling of his left upper eyelid that had lasted a month. He had no history of injury to the area.

During the examination, doctors noticed two firm, whitish projections beneath the swollen area near the inner side of the upper eyelid, the experts shared in the paper.

A computed tomography (CT) scan revealed a dense structure resembling a tooth, with a crown and root, originating from the roof of the left eye socket. It extended towards the tissues in front of the orbital septum, a thin barrier separating the eyelid from the deeper eye socket, and protruded outwards with two tooth-like points on its surface.

The projections' appearance and texture raised the possibility that they were teeth. Dr. Meghana Tanwar, a medical consultant at Aravind Eye Hospital, told Live Science that they had a “fairly smooth surface and were hard on palpation.”

The doctors surgically removed the structure. Examination confirmed that it was a mature canine tooth without teratomatous elements, consistent with an ectopic tooth in the upper part of the eye socket.

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What Is An Ectopic Tooth?

An ectopic tooth develops or emerges in an abnormal location. Some remain within the mouth but appear outside their usual positions in the dental arch, while others develop outside the normal arrangement of teeth.

The latter is particularly unusual. In this teenager's case, the tooth was located in the upper orbital region rather than within the normal dental arch.

Before confirming the diagnosis, doctors considered whether the projections could be associated with a teratoma, a type of tumor that can contain different tissues, including bone and tooth tissue. They also considered whether a foreign object might be lodged in the eyelid.

Imaging and examination of the removed structure helped establish that it was a mature tooth rather than tissue associated with a teratoma.

Why Is This Case Unusual?

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Ectopic teeth have been documented in several locations, including the nasal cavity, chin and maxillary sinus, an air-filled cavity within the cheekbone. Previous reports have also described teeth in the lower part of the eye socket.

However, the doctors said they could not find an earlier report of an ectopic tooth in the superior orbit, the upper region of the eye socket.

“To the best of our knowledge this is the first and only ectopic tooth reported in the superior orbit,” Tanwar told Live Science.

“This was a first not just for us but the world over,” she said of the case. “We were very surprised by it.”

What Causes Ectopic Teeth?

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The doctors could not determine why the tooth developed in this unusual location.

Possible explanations for ectopic tooth development include abnormalities during development, genetic factors, infections and physical trauma. However, the cause in this case remains unknown.

Imaging did not reveal any additional ectopic teeth. Tanwar said the likelihood of the teenager developing another such tooth was low.

Beth Dobbin, who represented Great Britain at the Tokyo Olympics in 2021, now spends more than 22 hours a day in bed.

The 32-year-old retired from athletics in April 2026, describing her illness as “serious” and “life-changing.” She was later diagnosed with myalgic encephalomyelitis (ME), a chronic condition with no known cure or specific treatment.

Dobbin reached the 200m semi-finals at the Tokyo Olympics and won bronze in the 4x200m relay with Scotland at the 2022 Commonwealth Games in Birmingham.

“It's life-decimating like I can't even put into words,” she said. “I feel like I've lost everything.”

Beth Dobbin's Diagnosis with ME

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Dobbin’s health began deteriorating after back-to-back COVID-19 and glandular fever infections in the winter of 2021-22, the BBC

reported.

She experienced worsening fatigue, slower running times and soreness in the glands in her neck and armpits. Initial tests by British Athletics doctors failed to identify the cause.

Despite her symptoms, she continued training in 2022. At the European Championships, she false-started after losing all feeling in her legs while in the starting blocks.

Her condition subsequently worsened. She struggled to stand and spent most of her time in bed. After consulting four or five specialists, she was diagnosed with ME.

Dobbin has been confined to her house and bed since then. She gets out of bed only to eat and use the bathroom. Even conversations, bright lights or loud sounds can trigger a “crash” lasting days or, in severe cases, months. She has left the house just five times this year, the report said.

She now leaves home mainly for medical appointments and blood tests. Even conversations, bright lights and loud sounds can trigger a “crash” that lasts days or, in severe cases, months. She has left home just five times this year, according to the report.

What Is ME?

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ME, also known as chronic fatigue syndrome (CFS), is a complex, chronic illness that can cause severe fatigue, pain, sleep disturbances and problems with thinking and memory. Symptoms do not improve simply with rest, and there is no established cure.

Dobbin rejects the term “chronic fatigue syndrome” because she believes it understates the severity of the condition.

“I wish it was just fatigue, that would be a walk in the park,” she said. “It's so much more than that. If I thought of fatigue in my top 20 symptoms it might just make the cut.”

She described the illness as feeling as though her entire body “is shutting down; it feels like you are a few days from death”.

More than 400,000 people in the UK are thought to have ME, although some estimates put the number above one million. The illness varies in severity, with some people continuing to work or study while others require extensive care.

Dobbin’s illness has also taken an emotional toll on her family.

“I'm just so desperate to help her but I can't because there is nothing. I'd take her anywhere, I'd take her to America if I had to, but there's nothing,” her father, Jim, said.

Beth Dobbin Aims To Raise ME Awareness

Dobbin describes her future as “very bleak” but hopes that greater awareness will lead to better treatment options.

The emergence of long COVID, which shares some symptoms with ME, has brought renewed attention to the illness and increased research funding.

She also wants to highlight the experiences of patients who are dismissed or disbelieved.

“A lot of people that have this illness that I've spoken to have said to me 'I don't get believed, people think I'm lazy'. I've never experienced one person that doesn't believe me and that's because, why would an athlete just suddenly stop after 20 years?”

Infections accounted for an estimated 2.3 million new cancer cases worldwide in 2024, or about 12% of all cancers diagnosed that year, according to a September 2026 study published in The Lancet Oncology. Among these, Helicobacter pylori (H. pylori), a bacterium that infects the stomach, was associated with an estimated 760,000 cancer cases.

A 2025 study by the International Agency for Research on Cancer (IARC), part of the World Health Organization (WHO), estimated that 76% of the 15.6 million stomach cancer cases expected over the lifetimes of people born between 2008 and 2017 could be attributable to H. pylori infection if prevention efforts do not improve.

Although infections can contribute to cancer development, they are not the only cause. Genetics, age and non-infectious factors also play a role, Dr. Vivek Kaul, Professor of Medicine in the Gastroenterology & Hepatology Division at the University of Rochester Medical Center, told HealthandMe in an exclusive interview.

“I think, generally speaking, I think H. pylori is a well-known carcinogen, mostly responsible for the development of gastric cancer,” Kaul said.

Is Cancer Increasingly Linked To Infections?

The findings highlight the contribution of infectious agents to the global cancer burden. However, Kaul cautioned against concluding that cancer is increasingly being driven by infections.

“But I don't think it's fair to say that, you know, we are moving towards a more infectious etiology for cancer,” he said.

“Cancer is a multifactorial disease state that develops, most commonly develops from genetic and from non-infectious causes,” Kaul added.

He explained that cancer development also depends on the ability of cells to defend themselves against external threats and genetic mutations.

“In many cases, cancer development comes primarily from genetic and age-related issues and boils down to the individual cell's ability, you know, to fight external attacks, such as from H. pylori type of agents or from genetic mutations,” he said.

Kaul also noted that other infectious agents have been implicated in cancer development.

How Does H. pylori Raise Stomach Cancer Risk?

H. pylori is a bacterium that infects the stomach lining and can persist for years. The infection can cause chronic inflammation and damage to stomach tissue, increasing the risk of gastric cancer.

According to scientists at the International Agency for Research on Cancer (IARC), part of the World Health Organization (WHO), H. pylori infection is responsible for an estimated 76% of stomach cancer cases worldwide. The infection often causes no noticeable symptoms, although some people may experience digestive complaints.

The bacterium can spread through contaminated food or water and close contact with infected individuals. In some cases, the infection can cause stomach ulcers. Because many infected people have no symptoms, testing may be needed to identify it.

Can H. pylori Infection Be Prevented From Progressing To Cancer?

The World Gastroenterology Organisation's global guidelines state that eradicating H. pylori before precancerous changes develop can help prevent gastric cancer. This evidence supports test-and-treat screening programmes for young adults in countries with a high disease burden and sufficient resources.

Testing can involve blood, breath or stool tests, depending on the clinical context. People diagnosed with the infection can receive treatment to eradicate the bacterium. Follow-up testing can then confirm whether treatment has worked.

Nobel laureate and gastroenterologist Dr Barry Marshall has also highlighted the potential for early treatment to reduce cancer risk.

“H. pylori is much more than an ulcer organism. If the infection persists for many years, it can cause chronic inflammation in the stomach and increase the risk of gastric cancer. That gives us an opportunity because this is a potentially preventable cause of cancer,” Marshall told PTI.

He stressed the need for wider testing, appropriate treatment and follow-up to ensure the infection has been cleared.

Other Digestive Cancers Are Also A Growing Concern

Beyond infection-associated cancers, Kaul highlighted the rising incidence of several digestive cancers.

“We know that esophageal squamous cancer is another example where we will be close to a million cases by 2035,” he said, pointing to the burden in East Asia, sub-Saharan Africa and South America, including India.

Kaul also identified liver cancer as a growing concern and noted the rise in colorectal cancer among younger people in Western countries. The increase in colorectal cancer among younger adults in the US contributed to recommendations to begin average-risk screening at age 45 rather than 50.

These trends underline the need to address infectious causes of cancer alongside other risk factors, while improving access to prevention, early detection and appropriate care.