To date, however, the interest and

To date, however, the interest and enthusiasm of the global public health community in both MERS and a MERS vaccine could be described as ambivalent. At last year's World Health Assembly in Geneva, Dr. Margaret Chan, the World Health Organization (WHO) Director General, announced that MERS- CoV is “a threat to the entire world”. However, later that sum- mer, a special WHO panel muted such sentiments by indicating that MERS did not yet constitute a “public health emergency of international concern” [1]. As of May 23, 2014, 635 laboratory- confirmed cases of MERS-CoV infection, including 193 deaths, had been reported to WHO from seven countries in the Middle East, two countries in Africa, six countries in Europe, two countries in Asia, and one country in North America [2].
More worrisome, 429 of these cases have been reported since March 27, 2014. A majority of these newly reported cases are secondary cases or cases with unknown exposure (Fig. 1), partly reflecting increased surveillance for this disease in Saudi Arabia, but also possibly suggesting an increased ratio of human-to-human transmission of MERS-CoV. Yet a group of WHO experts during a visit to Saudi Arabia failed to recommend any new public health measures beyond ongoing
surveillance for respiratory infections. Moreover, no new travel restrictions including restrictions on trade or the annual pilgrimage have been instituted [3]. Of course, this situation could change, pending new developments.
Similar to how the scientific community responded to the outbreak of severe acute respiratory syndrome (SARS) CoV that emerged from South China more than a decade ago, several promising avenues for developing a MERS vaccine have been explored. For now, however, many of us have received mixed messages on the urgency of advancing a vaccine development program for MERS-CoV.
In 1973, Harold Bloom, Yale University English professor and literary critic, published his famous book entitled The Anxiety of Influence: A Therory of Poetry. In essence, Bloom advances the hypothesis that poets aspire to write something truly original, but they become hindered in their creative processes by the influence, both conscious and unconscious, of previous works [4].
Anxiety of influence similarly affects virus researchers today because of a medical and scientific disaster that struck NIH and Merck investigators almost 50 years ago during the testing of a first-generation formalin-inactivated respiratory syncytial virus (RSV) vaccine [5]. The vaccine failed to pro- tect infants who received this vaccine in 1966e67, and many became sick from antibody-dependent enhanced respiratory signs and symptoms. Two young children died [6].
Since then, investigators working with experimental respi- ratory vaccines have proceeded with great caution and even reluctance based on the prospect of causing another such incident. In laboratory animals antibody-dependent immune