is a zoonotic infection circulating among small animals, usually black rats
and their fleas; it is caused by the bacillus Yersinia pestis. This
disease is transmitted from animals to humans by the bite of infected fleas,
direct contact, inhalation, and, rarely, ingestion of infective material.
Untreated plague has a high case-fatality rate (1,2).
pestis is a global pathogen that has active foci in all continents
except Australia and Antarctica (3).
Plague represents an exotic disease in North America; it usually affects
prairie dogs (Cynomus luduvicianus) and has eliminated large colonies
of these animals in the northwestern United States. Although these animals are
susceptible, it is believed that other rodents and their fleas are the
reservoirs and spread the disease during epizoonotics and maintain the
forms of plague are known: bubonic, septicemic, and pneumonic. The bubonic
form is most common and results from the bite of an infective flea. The
bacillus enters through the bite, travels through the lymphatic system to the
lymph nodes, and results in painful inflammation. The septicemic form occurs
when the infection spreads through the bloodstream. The pneumonic form results
from inhalation of aerosolized infective droplets and can also be transmitted
between humans (1,2).
plague, historically also known as Black Death, swept across Europe during the
late medieval period in an epidemic that started in 1347 (5–9).
The disease got its name from the deep purple, almost black discoloration of
infected persons caused by subcutaneous hemorrhages. Wars, poverty, hunger,
and malnutrition made Europe of the 14th century an ideal ground for plague
epidemics. The first major outbreak occurred in Sicily in 1347, spread through
Europe, and killed nearly half of the population (≈25 million persons)
in 3 years. The disease became endemic and haunted the continent throughout
the 14th–18th centuries. Major outbreaks occurred in Italy in 1629, London
in 1665, and Vienna in 1679 (5–9).
is not known where the pandemic started. It most likely originated in central
Asia and was carried west by Mongols and traders along the Silk Road. It was
imported to Europe through Crimea, from which it spread to Sicily. The total
number of deaths worldwide from the pandemic is estimated to be 75 million (5–9).
rat-borne plague has been controlled since the beginning of the 20th century
by modern sanitation practices. Epidemics caused by rats transferred on ships
to port cities are no longer a threat. However, the disease still occurs in
rural areas because Y. pestis infects various wild rodents (1,2).
continuing potential for reemergence of plague is evident by reports of
outbreaks of the infection in Africa and India. The World Health Organization
reports 1,000–3,000 new cases every year in impoverished rat-infested rural
areas of Africa, Southeast Asia, and South America (1,2).
However, an investigation has created some doubts about the nature of Black
Death by implicating other possible causes such as Ebola-like viruses or other
infectious agents (10).
1347, when plague appeared in Europe, and especially after 1493, when syphilis
was observed in Europe, theories on infectious and communicable diseases were
formulated. Many scientists during these times developed ideas of contagion,
which had an effect on public health regulations and the structure of cities.
Moreover, decisions on plague control during that period reinforced the idea
of public health measures for prevention of infectious diseases, an idea that
was previously vague.
the 11th century, Venice, a naval and commercial power, had a special interest
in the Eastern Mediterranean and later took advantage of the redistribution of
the land of the Byzantine Empire after the Fourth Crusade (1204). Gradually
and through conflicts after this crusade, this city-state on the Adriatic Sea
gained control of the Ionian Islands, Crete, and some coastal cities of
mainland Greece and established a network of trading posts. The islands of
Corfu (Greek name Kerkyra), Zante (Zakynthos), Cephalonia, and Leukada were
incorporated into the Venetian State in 1386, 1485, 1502, and 1684,
respectively, and remained part of it until its demise in 1797 (11).
study investigates plague on the 4 islands during the 17th and 18th centuries.
This period was selected because after the second half of the 17th century
plague was observed only sporadically with limited epidemics. Plague was last
observed in Venice in 1630, whereas in southeastern Europe, plague was
observed until the 19th century (12).
During the early 18th century, changes took place in the Venetian health
policies, and the strategic and economic role of the islands increased after
the gradual loss of the great trade routes of the Mediterranean Sea.
4 large islands in the Ionian Sea are a useful area for research because
they had been under Venetian rule and were located just off the western
coast of mainland Greece. This location made them a gateway to and from the
Ottoman Empire and a frontier of Venice to the East. However, despite their
proximity to mainland Greece, political and institutional differences were
substantial between these islands and the neighboring Greek coast that was
under Ottoman rule. Research regarding plague in this area has been limited.
Moreover, comparisons of Venetian health policies regarding plague and their
effectiveness on the Ionian Islands with those of neighboring Greece have
not been made.
study had 4 goals. The first goal was to identify epidemics of plague that
struck the Ionian Islands during the 17th and 18th centuries. The second
goal was to reconstruct the course of the epidemics. The third goal was to
highlight differences in the prevalence of infection on the Ionian Islands
during the 17th and 18th centuries and discuss the epidemiologic status of
the islands compared with that of the neighboring coast of the Greek
peninsula. The fourth goal was to investigate and describe measures taken by
the Venetian authorities on these islands against plague during the study
research was conducted in the Venetian state archive (Archivio di Stato di
Venezia). Unpublished archival material dealing with the Ionian Islands during
the 17th and 18th centuries was investigated with emphasis on periods of
epidemiologic crises. We studied the following: 1) total number of registers
of legislative bodies of the Venetian Republic (Senato mar and Senato rettori)
for 1600–1797 to locate laws dealing with curtailment of plague and
organization of health services on the Ionian Islands, 2) daily correspondence
of Venetian authorities of the islands with Venice through the proveditori da
terra et da mar and senato (secreta) dispacci rettori, and 3) archives of the
Venetian health inspectors (provveditori alla sanità) regarding the Venetian
health policy for the Ionian Islands. Additionally, several historical sources
providing information about plague epidemics in the Mediterranean area during
the 17th and 18th centuries were reviewed. This investigation was related to
the doctoral dissertation of this article's first author (K.K.), a historian
at the University of Athens. This dissertation (13)
reviews the subject historically. This article examines the subject from
medical and epidemiologic points of
sources show that most cases of plague on the Ionian Islands during the 17th
and 18th centuries were imported from the neighboring coast of mainland
Greece and ports in the southwestern Ottoman Empire. Only 2 epidemics were
imported from the trade routes of the Mediterranean Sea. Of 11 epidemics, 8
occurred during the 17th century and 3 occurred during the 18th century.
Plague struck Corfu in 1611, 1630, 1648, and 1673; Zante in 1617, 1646,
1692, and 1728; and Cephalonia in 1646 and 1760. Leukada had a disastrous
epidemic in 1743, a few decades after the island became part of the Venetian
the 18th century, plague had waned despite an outbreak along the
southwestern coast of the Ottoman Empire, a short distance from the coasts
of the Ionian Islands. In the 18th century, the southern Balkans had
repeated waves of plague in 1718–1720, 1728–1731, 1733–1740,
1756–1765, 1782–1784, 1787–1789, and 1790–1793 (13).
Only 14 plague-free years are described for the Greek peninsula during the
18th century (14).
These epidemics affected cities and villages in western Peloponnese and
western mainland Greece, which, because of trade, were in constant contact
with the Ionian Islands. Because of commercial interests, contact between
inhabitants of the islands and mainland Greece could not be halted. However,
vigorous attempts by Venetian authorities stopped all communication between
these areas during plague outbreaks.
these conditions, waning of plague epidemics during the 18th century may be
attributed to sanitary measures taken by the Venetian government. These
measures, among other regulations, dictated strict control of population
movements, particularly during periods of epidemiologic crises. The efficacy
of these measures is better appreciated because plague during the 17th
century spread from lazzarettos (institutions where those with plague or
other similar diseases were isolated) mainly because of negligence. In
contrast, 2 of the 3 epidemics during the 18th century were caused by
incorrect diagnoses or delayed notification of the authorities. Success of
these measures became apparent in Corfu where plague was eradicated after
1673, only to reappear during British rule in the early 19th century (13).
The importance of Corfu to Venice, particularly after the loss of Crete in
1669, resulted in creation of an effective invisible wall against plague
until the end of the Venetian domination in 1797.
city-states of northern Italy, including Venice, organized their defense
against plague from the time of the Black Death (9).
Experience and observation provided the first tools against epidemics
because scientific information about the cause of plague was not obtained
until several centuries later at the end of the 19th century, through
laboratory research conducted by Alexandre Yersin (15).
The Venetian State, on the basis of the belief in the miasmatic and
contagious nature of plague and being a pioneer in organization of public
health services conceived in the late Middle Ages, established regulations
and practices in the city of the Doges and its conquests. These regulations
and practices included quarantine (period of isolation ranging from 14 to
>40 days and occasionally even longer, depending on the health of the
port of origin), lazarettos, public health offices, and cordoni di sanità,
which on the Ionian Islands were coastal garrisons that controlled access to
Venetian territories (16).
sources showed that health board officers in Corfu and Zante were initially
elected around 1545. However, it is likely that health boards had previously
existed. The first lazzarettos were established in Corfu and Zante in 1588
and in Cephalonia and Leukada at the beginning of the 18th century.
Venetian health policy was reformed in the 18th century. These reforms
likely emphasized disease prevention and dealt with health emergencies (17).
The new policy was based on daily reports of health conditions on the
islands and suspicious areas in the eastern Mediterranean, and included
creation of a common public health framework (identical laws for plague
control, decrees, and institutions and infrastructures) for all islands.
This policy would facilitate interventions and change the way in which local
health officers were selected.
main goal of these reforms was improvement of the structure and function of
lazzarettos. During the 18th century, new lazzarettos were established, and
existing ones underwent extension and changes. In 1726, a new statute
defining the obligations and responsibilities of the heads of the
institutions was introduced. According to this statute, during periods with
no or low disease activity, lazzarettos referred directly to Venetian
authorities and bypassed authority of local health boards (13).
these new regulations, Venetian archives reported occasional problems in
health services of the islands because of poorly trained health officers,
who were elected from the local upper class and were eager to acquire
greater political autonomy. This situation resulted in conflicts between
Venetian representatives and local health officials, as well as between
local factions known as cittadini (18).
show that until the end of the Venetian rule on the Ionian Islands,
lazzarettos functioned as protective shields for Venice and transferred
responsibility of plague control from Venice to peripheral areas (19).
When there was evidence or even suspicion that plague was present on an
island, all links to Venice were immediately discontinued for the duration
of the threat. Islands were isolated by order of the senato, and trade
commenced only after the state of emergency had ended. During these periods,
the Venetian government did not intervene in the responsibilities and
actions of local health inspectors because such intervention could provoke
social unrest (13).
Thus, the cost for Venice was minor. However, this action did not indicate
negligence by the state mechanism each time plague affected an island and
was based on widespread use of an information network of daily reports of
Venetian consuls in Mediterranean areas to Venetian authorities, detailed
interrogation of sailors who arrived in Venetian ports, effective control of
all local movements in plague-infested areas, and activation of the cordoni
di sanità. Additionally, when plague occurred, residents were separated by
health authorities into groups of healthy and sick persons regardless of
social hierarchies. Persons affected by plague were kept in lazarettos, and
large numbers of infected persons were kept in hospitals, houses, or
neighborhoods on the assumption that plague in these persons remained
isolated. Isolation was ensured by military force. Thus, plague-stricken
areas resembled a large institution under constant inspection and
surveillance and disconnected from the rest of society (13).
contrast to measures taken on the Ionian Islands during the 17th and 18th
centuries, mainland Greece, which was under Ottoman rule, had a different
mentality in dealing with plague. Isolation of patients and quarantine were
not common practices. Thus, plague continued to cause epidemics in mainland
Greece during the first half of the 19th century. These epidemics had
devastating demographic and financial consequences. After 1830, when the
Ottoman administration implemented sanitary measures such as quarantine,
spread of plague in mainland Greece decreased substantially (20).
modern medical regimens can successfully treat patients with plague and stop
its spread, prevention and isolation policies can contribute to control of
this disease. This finding has been demonstrated by successful management of
a plague epidemic in Surat, India, in 1994, in which prevention techniques
similar to those used during Venetian rule were used (21).
conclusion, although the scientific basis of plague was not known, the
Venetian administration recognized the infectious nature of this disease and
took successful measures that dramatically decreased the spread of the
plague epidemic on the Ionian Islands during the 18th century. The results
of these measures are more impressive if compared with those in the
neighboring coastal region of the Greek peninsula, which under Ottoman rule
had endemic plague during the same period. Results of the present historical
investigation lead to the conclusion that even in the absence of scientific
knowledge, observation and well-organized public health services can
effectively restrain infectious outbreaks to the point of disappearance, as
occurred with plague in Corfu during the 18th century.
Dr Konstantinidou is a
lecturer of history in the Department of History and Archaeology at the
National and Kapodistrian University of Athens. Her research interests
include the history of Greek territories under Venetian rule.
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