INTRODUCTION: Typhoon Haiyan, or Typhoon "Yolanda" in the Philippines, caused catastrophic damage last November 8, 2013 in the islands of Leyte. As of April 17, 201, NDRRMC confirmed 6,300 fatalities across the country and around 5,877 were from Eastern Visayas. The actual death toll remained unclear although it is being claimed to be about 10,000 in Tacloban City alone.

OBJECTIVE: This study aimed to determine the transmission of notifiable diseases under PIDSR as to increase in morbidity, deaths and case fatality rates among patients consulted and/or admitted at EVRMC before and after ST Yolanda.

MATERIALS AND METHODS: This is a descriptive study which included all patients who sought consultation and/or admission in EVRMC with clinical diagnosis of any notifiable disease under the PIDSR reference list.

RESULTS: A cumulative total of 8,299 patients with notifiable diseases sought and/or admission between November 2012 - October 2013 and November 2013 - October 2014. Of which, 3,873 or 46.67% were cases before Super Typhoon Yolanda while 4,426 or 53.33% were cases a year after. Patients below 14 years old were mostly affected after the disaster. There were few patients, 70 years old and above who sought consultation and/or admission. As to occurrence between sexes, there were more females affected than males after the disaster which comprised of 51.4% of the total. As to geographic distribution, there were more cases coming from the 1st district of Leyte including Tacloban City comprising 61.58% compared to its occurrence prior to the disaster.  As to the number of cases under Category I, an increased cases of measles from 2 cases to 356 or an increase of 99.44% after the disaster. Notifiable diseases under Category II comprised 91.53% of the total post disaster with an increase of 12.5% from the total cases the previous year. Acute watery diarrhea had the highest number of patients affected then, was followed by Dengue fever,  27.43% and Acute bloody diarrhea, 2.35%. Chikungunya increased from 10 cases the previous year to 33. As to deaths, there was no increase under Category I but, under Category II, an increase of 26.1% after the typhoon was observed. Among these, were Acute watery diarrhea, Dengue fever, Influenza like illness and Measles after disaster.

CONCLUSION: During calamities, everything is affected, from infrastructure, agriculture and most of all the people. Transmission of different infectious diseases occur because of displacement of the population, lack of safe water supply and sanitation facilities and, lack of available health care services.