Black widows spiders are notorious for their powerful venom and gruesome mating habits, which sometimes involves the females killing and eating the males after procreating.
There are 31 species of these spiders, which all belong to the genus (group of species) Latrodectus, data from the Integrated Taxonomic Information System (ITIS) shows.
Black widows are found around the world in temperate regions, including parts of the United States, Europe, Asia, South America, Australia and Africa.
They live solitary lives until the mating season comes around and it is time to pair up with a member of the opposite sex.
The spiders are named after the predilection of the females for killing their male counterparts after mating. The females often eat the males after killing them, with scientists speculating that this act provides them with a source of protein.
In the wild, black widows can live for up to three years, although the males tend to have much shorter lives as a result of this bizarre mating behavior.
Adult female black widows measure around half an inch in length and are usually more than double the size of the males of their species, although they can sometimes be up to 20 times larger, according to a report entitled “Black Widow Spider Toxicity” published this year by scientists from The Brooklyn Hospital Center and St. Luke’s University Health Network.
The females can be easily identified by their shiny black bodies and the characteristic hourglass-shaped mark located on the lower side of the abdomen, which can range in color from yellowish orange to red, according to the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA).
Males can be grey or black in color and feature red or pink spots on the upper side of the abdomen.
Only the female spiders pose a risk to humans, with venom that is thought to be around 15 times more potent than that of a rattlesnake. Indeed, black widows are considered to be the most venomous spiders in North America.
But despite the popular perception, black widow bites are rarely fatal. In the United States, around 2,600 black widow bites on humans are reported every year, with only 1.4 percent of these cases experiencing severe symptoms, data from the Black Widow Spider Toxicity report shows.
While they are rarely fatal, a bite from these spiders can still be a painful experience. The venom can cause strong muscle pain, nausea, profuse perspiration, increased blood pressure, fever and mild paralysis of the diaphragm, which can make it difficult to breathe.
Pain from the bite can persist for between eight to 12 hours, while some symptoms may last for several days—although most people make a full recovery.
Those most at risk from black widow bites are small children, the elderly or people who are very sick.
A new study has found higher numbers of anti-SARS-CoV-2 antibodies in older males who required hospitalization for COVID-19.
Scientists have found that being hospitalized with COVID-19, as well as being male and of older age, increases the chances of a person having high plasma levels of antibodies that can protect against the disease.
This plasma, which is a component of blood, may help treat the disease in others.
The research, which features in the Journal of Clinical Investigation, is the first step toward confirming whether blood plasma therapy is effective in treating COVID-19.
As scientists continue to search for an effective vaccine for SARS-CoV-2, the virus that causes COVID-19, treatments that can reduce the risk of death are crucial for lowering the mortality rate associated with the disease.
However, to date, research has shown few treatments to be effective.
Furthermore, a major study by the World Health Organization (WHO) — currently available as a preprint — found that remdesivir, the most promising treatment for COVID-19, appears to make no significant difference to the mortality rate.
One possible treatment that may be effective is antibody therapy through convalescent plasma infusion.
Antibody therapies work by infusing a person who has an infection with the plasma of a person who has overcome that infection. The plasma of the person who has recovered may contain antibodies that their body created in response to the initial infection.
Research has suggested that this may be effective in treating people with COVID-19, and observational studies have, so far, produced promising results. However, further research is necessary to confirm these initial findings.
For this research to proceed, however, scientists need a greater knowledge of the makeup of the blood plasma that the process uses so that they can develop a standardized approach to the treatment.
To contribute to this goal, the scientists behind the present article conducted a study to determine what effect age, sex, and the severity of the disease had on the size and overall quality of a person’s antibody response to SARS-CoV-2.
This is important as the antibody response that COVID-19 induces can vary significantly. The scientists behind the present study suggest that this may be because antibodies are typically linked to disease severity, and COVID-19 symptoms can range from undetectable to life threatening.
Determining what factors lead to blood plasma containing antibodies of good quantity and quality may make it easier to standardize and optimize the treatment.
The study involved 126 adults who had recovered from a COVID-19 infection. The researchers took blood from the participants, as well as information regarding their age, sex, and whether they required hospitalization for the disease.
The scientists analyzed the plasma’s ability to neutralize the cells of SARS-CoV-2 in cell cultures. They also used commercially available tests to determine the level of antibodies.
They found that a strong antibody response was associated with hospitalization for