Should screening for dengue be mandatory before blood transfusion?
I recently came across a story in The Muscat Daily (Jan. 23, 2019) which said “the Ministry of Health (MoH) and the Department of Blood Banks Services in Oman have announced on their Twitter accounts that “those affected by dengue virus will not be allowed to donate blood for six months”. Dengue cases are being reported in the country. The latest figures by the Ministry of Health revealed that until January 22, there were 52 recorded cases of dengue fever. In a statement, MoH said, “As a precautionary measure to prevent the spread of the infection, residents and citizens of the dengue-affected areas will also not be allowed to donate blood for 28 days.” According to the Ministry, this is being put in place to help “prevent others from contracting the disease”.
Travel is a risk factor for spread of any infectious disease. With increasing travel, there is a chance of the disease appearing in another part of the country or the globe, where it did not occur previously. Consequently, the prevalence of dengue has increased several-folds across the world.
The dengue virus was recognized as a transfusion-transmitted pathogen in 2008 (World J Virol. 2015; 4(2):113-23). Chikungunya virus is also a transfusion-transmissible infection, as per the World Health Organization (WHO).
Since then, there has been concern about the risk of transmission of dengue via blood transfusion. Dengue virus becomes a blood-borne pathogen during the period of viremia, which coincides with the febrile period (World J Virol. 2015; 4(2):113-23).
“In 2009, the American Association of Blood Banks placed dengue virus in the highest category of emerging infectious agents for their potential impact on transfusion recipient safety for the next years in North America” (World J Virol. 2015; 4(2):113-23).
Although rare, cases of transfusion-transmitted dengue fever have been reported. So far, five cases of transfusion-transmitted dengue, including one case of dengue hemorrhagic fever, have been formerly documented (World J Virol. 2015; 4(2):113-23).
Blood donors have been recognized as likely vehicles for transmission of the infection in endemic areas.
Dengue has become endemic in India, particularly in Delhi, where it has become a perennial infection.
In a study conducted to determine the prevalence of dengue virus infection in blood donors in a tertiary care centre, high seroprevalence (58%) of dengue infection in healthy asymptomatic blood donors was found; but, no active viremia was detected (J Clin Diagn Res. 2016;10(10): DC08–DC10).
Seroprevalence is still a risk to blood safety and is a potential source for transfusion-transmitted infections.
NACO National Blood Transfusion Council “Guidelines for Blood donor selection and Blood Donor Referral 2017” recommend that blood donation should be deferred for 6 months following full recovery in case of history of dengue or Chikungunya. A person who has visited a Dengue and/or Chikungunya endemic area is deferred for 4 weeks following return from the endemic area if no febrile illness is noted.
In its 2012 “Guidelines on Assessing Donor Suitability for Blood Donation”, the WHO also recommends that individuals with a history of dengue or chikungunya virus in endemic areas should defer for 6 months following full recovery from infection. It further says that individuals who have visited an area endemic for dengue or chikungunya should defer for 28 days following return. And, those who have suffered a febrile illness during or following return from an endemic region should defer for 6 months following full recovery from infection
Dr NK Bhatia, Medical Director, Mission Jan Jagriti Blood Bank is a renowned name in blood banking with more than three decades of experience the field. According to Dr NK Bhatia, “Dengue patients are not allowed to donate blood for one year after treatment. If there is a history of blood/blood products transfusion, the same deferral period applies. This is also true for Chikungunya patients. Any person who has a ‘normal’ viral fever is not allowed to donate blood for 7 days after the active phase is over. Some extend this duration to one month.”
Hence, a medical history becomes very important when assessing eligibility of a prospective blood donor.
Always ask a history of dengue/Chikungunya, history of blood/blood product transfusion and history of any viral fever.
Dengue patients should defer blood donation for up to 6-12 months post-infection.
But, a question then arises “Should screening for dengue be mandatory before blood transfusion as is for hepatitis B virus, hepatitis C virus, HIV, syphilis, malaria” as many dengue patients go undetected in acute febrile illness?