Preface

Chapter 7 **Epidemiology of Vitamin B12 Deficiency 103**

**VI** Contents

Chapter 8 **β-Thalassemia: Genotypes and Phenotypes 113**

Laila Sherief and Marwa Zakaria

Tekin Guney, Aysun Senturk Yikilmaz and Imdat Dilek

Tamer Hassan, Mohamed Badr, Usama El Safy, Mervat Hesham,

Preventable diseases among cross-cultural communities are rampant, causing untold human suffering, and consequently untimely premature deaths occur particularly in poor-resource settings. These human sufferings, including deaths, can be reduced or avoided by applying routine principles of hygiene in individuals' lives as some of them are purely simple rem‐ edies, which are inexpensive, affordable, acceptable and easily accessible. Generally, it is an individual's responsibility to guard the different aspects of his or her own health, conse‐ quently resulting in a positive change in the lifestyle and good health-seeking behaviour.

It is in the view of the authors that the readers of this book will derive maximum benefits from it and act as change agents in their places of work and the communities they live or serve. It is evident that change is first enacted from within the mindset of an individual, then transmitted to families, groups and communities, and eventually the mindset of a na‐ tion can change creating an environment which is better for everybody to live in.

This book contains chapters discussing conditions or diseases that may not be common in the readers' area. Caution as such may never be underestimated considering the fact that we are living in a global village where one can never say 'this does not occur in my area' but rather question, does this occur in my community, why does it occur, who is affected, where and when does it occur and what can be done about it? These questions constitute what epidemiology is all about, and their precise and comprehensive answers can transform lives and help us have the right perceptions for the health challenges we face and accept the pos‐ sibility of dealing with them directly. It is only when we can all jointly acknowledge and accept that 'this is our problem' as opposed to 'it is theirs' that this notion can help us deal with the 'epidemiology of communicable and non-communicable diseases: attributes of life‐ style and nature on humankind'.

#### **Fyson H. Kasenga, PhD, MPH** Malawi Adventist University Malamulo College of Health of Sciences

Makwasa, Malawi

**Epidemiology of Communicable Diseases**

#### **Epidemiology and Investigation of Foot‐and‐Mouth Disease (FMD) in the Republic of Korea Epidemiology and Investigation of Foot**‐**and**‐**Mouth Disease (FMD) in the Republic of Korea**

Hachung Yoon, Wooseog Jeong, Jida Choi, Yong Myung Kang and Hong Sik Park Hachung Yoon, Wooseog Jeong, Jida Choi, Yong Myung Kang and Hong Sik Park

Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/63975

#### **Abstract**

This chapter describes about the experience of dealing with FMD outbreaks in the Republic of Korea. We explain what is FMD, the concept of epidemiological investiga‐ tion on outbreak sites of FMD, including the episode of detecting the index case for seven epidemics occurred since 2000, and information obtained from investigation in Korea. In any case, farmers' attitude (recognize clinical signs and report suspected cases) played the essential role in determining size and duration of epidemics. A rapid and correct diagnosis including clinical examination and laboratory test for confirmation is also important.

**Keywords:** foot‐and‐mouth disease (FMD), investigation, control measures, surveil‐ lance, Republic of Korea

## **1. Introduction**

Foot‐and‐mouth disease (FMD) caused by virus infection of a small non‐enveloped ribonucleic acid (RNA) virus belongs to family Picornaviridae, genus Aphthovirus. FMD virus affects Cloven‐hoofed domestic animals including cattle, pig, sheep, goat, deer, boar, and wild animals. Due to its high contagiousness, FMD has a great potential for causing severe economic loss. There are seven immunologically distinct serotypes of FMD virus: O (Oise Valley), A (Allemand), C, Asia1, SAT (southern African territories)‐1, SAT‐2, SAT‐3. According to the homogeneity of gene sequence of VP1 protein (approximately 639 base pairs, bps), the virus' topotype (concerns to the location) and lineage (concerns to the ancestor) are further catego‐

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

rized. RNA viruses show frequent spontaneous mutation, which results in emergence of new lineages. Phylogenetic analysis allows tracking the evolution and the origin of strains [1].

Clinical signs of FMD are characterized by vesicles in foot, mouth, and teats. Virus starts excreting 2 days before the appearance of clinical signs (4 days in case of milk), and antibody can be detected from 3‐5 days after the appearance of clinical signs. High levels of antibodies are reached 2–4 days later and remained for many months. The virus disappears upon the appearance of antibody in most parts of the body. However, it continues to be detected exceptionally in laryngo‐pharyngeal fluid. Antibodies to FMD virus are directed against structural proteins (SP) in the viral capsid and non‐structural proteins (NSP) in the process of virus replication. SP antibodies are relatively serotype specific and induced by both vaccination and infection. Meanwhile, NSP antibodies are not serotype specific and induced by infection but rarely by non‐purified vaccine also. SP antibodies usually start to appear approximately 3–4 days after the appearance of clinical signs, while 6–7 days in case of NSP antibodies [2, 3].

FMD occurs throughout the world, mainly in countries of Asia, Africa and parts of South America. It is the first disease for which the OIE (World Organisation for Animal Health) established an official list of free countries upon the science‐based standards, guidelines and recommendations [4]. The Republic of Korea had been free from FMD without vaccination for the past 66 years, before a the outbreak of FMD in March 2000. In this chapter, epidemics of FMD in Korea from 2000 to 2015 are described together with their epidemiological character‐ istics.
