The latter view is frequently supported in the scientific community, particularly among veterans of the WHO Smallpox Eradication Program.On March 31, 2003, smallpox scabs were found inside an envelope in an 1888 book on Civil War medicine in Santa Fe, New Mexico. The envelope was labeled as containing scabs from a vaccination and gave scientists at the CDC an opportunity to study the history of smallpox vaccination in the United States. On July 1, 2014, six sealed glass vials of smallpox dated 1954, along with sample vials of other pathogens, were discovered in a cold storage room in an FDA laboratory at the National Institutes of Health location in Bethesda, Maryland. The smallpox vials were subsequently transferred to the custody of the CDC in Atlanta, where virus taken from at least two vials proved viable in culture. After studies were conducted, the CDC destroyed the virus under WHO observation on February 24, 2015.In 2017, Canadian scientists recreated an extinct horse pox virus to demonstrate that the smallpox virus can be recreated in a small lab at a cost of about $100,000, by a team of scientists without specialist knowledge. This makes the retention controversy irrelevant since the virus can be easily recreated even if all samples are destroyed.
Sometimes, breakthrough bleeding is classified as abnormal and thereby as a form of metrorrhagia, and sometimes it is classified as not abnormal.In the context of hemophilia, the term describes a bleeding that occurs while a patient is on prophylaxis. Presentation
The bleeding is usually light, often referred to as "spotting," though a few people may experience heavier bleeding.It is estimated that breakthrough bleeding affects around 25 % of combined oral contraceptive pill (COCP) users during the initial 3 to 4 months of use, it then usually resolves on its own. Mechanism
Breakthrough bleeding is commonly due to 4 factors: physiologic effects  of  OCs  on  the  endometrium,  OC-related  parameters,  (dose, formulation,  and  regimen),  patient behavior, (compliance,  using concomitant  medications,  and  smoking) and benign or malignant pathology. Treatment
Breakthrough bleeding that does not resolve on its own is a common reason for women to switch to different pill formulations, or to switch to a non-hormonal method of birth control. Terminology
Metrorrhagia is from metro = measure, -rrhagia = abnormal flow. The term is no longer recommended. See also
Menometrorrhagia
Istihadha
Menstruation
Menstruation in Islam
Postcoital bleeding
Vaginal bleeding
Withdrawal bleeding
Culture and menstruation

References


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