Thursday 11 September 2003, 4pm, Chapel
Urbanisation, disease, giraffes
Tim Dyson, London School of Economics
In historical times, urban areas were demographic 'sinks' - with higher death than birth rates. The reason was that infectious diseases thrived in towns. The process of urbanisation in Europe, and later other world regions, was enabled and to a considerable extent caused by sustained mortality decline.
HIV/ AIDS is an infectious disease, and levels of HIV prevalence tend to be appreciably higher in urban areas. This paper shows that within world regions which are relatively homogenous with respect to their experience of HIV/ AIDS, variation in the level of urbanisation corresponds to about one third of variation in estimated HIV prevalence. Furthermore, for populations in the world's worst affected area - eastern and southern Africa - there are signs that, partly by differentially raising urban death rates and depressing urban birth rates, HIV/ AIDS is slowing the pace of urbanisation. Also, in countries with high loads of HIV and relatively low birth rates, like South Africa, it will not be long before the urban sector constitutes a demographic 'sink'.
The nature of causation in social processes is such that they are never exactly reversed. Nevertheless there is a strong element of reversal here. If the trees in east Africa were to slowly disappear, the giraffe would not evolve into its predecessor; but it probably would end up with a shorter neck.
Development Studies Institute (DESTIN)
London School of Economics
Houghton Street
London WC2A 2AE
Email: T.Dyson@lse.ac.uk
Influenza in China 1918-19 and the possible significance of the Chinese Labour Corps in the development of the 1918-19 influenza pandemic
Christopher Langford, London School of Economics
This paper seeks to establish whether China, like most countries, experienced an influenza outbreak in 1918-19, and gauge its extent and severity. It also attempts to evaluate the suggestion that the 1918-19 influenza virus originated in China, and was carried to France by Chinese migrant workers during the First World War.
Statistical and other materials for Hong Kong and Shanghai are examined and non-statistical materials for elsewhere in China, as well as British archival records relating to the recruitment and transportation to France of Chinese workers. Influenza was widespread in China in 1918-19, but although severe in some parts, was mild in many places, compared with elsewhere in the world. The most likely explanation is that the 1918-19 influenza virus, or closely-related precursor, had originated in China, so that many Chinese had prior exposure and hence some immunity. It is plausible that Chinese workers en route to France carried this virus with them, leading to the pandemic.
Department of Social Policy
London School of Economics
Houghton Street
London WC2A 2AE
Email: C.Langford@lse.ac.uk
Mortality change in Kazakhstan and central Asia in the 1990s: a tale of two transitions
Francesca Taylor, United Nations Population Fund (UNFPA) and Arjan Gjonça, London School of Economics
Kazakhstan is a vast, multi-ethnic former Soviet Union republic (FSU) in central Asia. Since its independence in 1991, it has experienced a sharp escalation in mortality, roughly paralleling that which occurred in Russia.
This paper examines recent trends and patterns of death in Kazakhstan, along with those of its central Asian neighbours, Russia and some of the other former Soviet Union states. The analysis of the data shows that no other central Asian republic (CAR) has experienced such a dramatic rise in the death rate during transition, as has Kazakhstan. Moreover, most aspects of its excess mortality are similar to those observed in Russia in the 1990s. Male hyper-mortality is a key feature. Unlike most mortality crises when the young and elderly are hardest hit, the prime adult ages have been most affected.
The final part of the paper explores reasons for acute rise in the death rates in Kazakhstan, and includes a regional analysis of mortality. As for Russia, its causes are complex. Without doubt, Kazakhstan suffered a particularly severe economic recession. The ensuing stress seems to have exacerbated pre-existing unhealthy behaviours, particularly 'binge' drinking. However, the ethnic composition of the population and the proximity to and the influence of Russia are the more underlying factors crucial to an understanding of Kazakhstan's mortality and why it now deviates significantly from that of its central Asian neighbours.
Email: ftaylor@unfpa.org
Department of Social Policy
London School of Economics
Houghton Street
London WC2A 2AE
Email: a.gjonca1@lse.ac.uk